KNX Basic exam questions — medium level

KNX Basic mock exam questions selected at medium level. Ideal for consolidating what you’ve learned and gauging your real level.

226 questions~ 203 minMedium

Medium level questions

Q01
ETS is available in four versions. Which statement is correct?
- A.ETS Lite allows an unlimited number of devices
- B.ETS Professional is limited to 20 products
- C.ETS Home allows one project with a maximum of 64 KNX devices
- D.ETS Home allows an unlimited number of projects
KNX System Arguments· KNX advantages & ETS editions· Medium
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Correct answer
C — ETS Home allows one project with a maximum of 64 KNX devices
Learning tip
Correct: ETS Home = 1 project, max 64 devices.
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Q02
ETS Lite is limited to projects with how many products, and is primarily intended for whom?
- A.Up to 64 products — for homeowners
- B.Unlimited products — for professional integrators
- C.Up to 100 products — for manufacturers
- D.Up to 20 products — primarily for certified training centres
KNX System Arguments· KNX advantages & ETS editions· Medium
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Correct answer
D — Up to 20 products — primarily for certified training centres
Learning tip
Correct: up to 20 products, mainly for certified training centres.
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Q03
In 1999 the EIBA merged with two other European associations. Which ones?
- A.CENELEC (Belgium) and CEN (France)
- B.BCI (France, Batibus) and the European Home Systems Association / EHSA (Netherlands, EHS)
- C.LonMark (USA) and BACnet (Germany)
- D.DALI (Germany) and Batibus (Netherlands)
KNX System Arguments· KNX history & standardization· Medium
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Correct answer
B — BCI (France, Batibus) and the European Home Systems Association / EHSA (Netherlands, EHS)
Learning tip
Correct: BCI (France, Batibus) and EHSA (Netherlands, EHS).
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Q04
The KNX Association started with how many members, and roughly how many does it have today?
- A.Started with 3 members, now over 100
- B.Started with 15 members, now over 1000
- C.Started with 50 members, now over 5000
- D.Started with 9 members, now over 500
KNX System Arguments· KNX history & standardization· Medium
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Correct answer
D — Started with 9 members, now over 500
Learning tip
Correct: started with 9 members, now over 500.
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Q05
Which statement about S-Mode (System Mode) is correct?
- A.It is configured without a PC using push buttons
- B.It is limited to small installations only
- C.It requires a different software tool for each manufacturer
- D.It uses the manufacturer-independent ETS software on a PC and suits installations of any size
KNX System Arguments· KNX media & configuration modes· Medium
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Correct answer
D — It uses the manufacturer-independent ETS software on a PC and suits installations of any size
Learning tip
Correct: ETS on a PC, manufacturer-independent, any installation size.
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Q06
KNX interworking (devices from different manufacturers cooperating) relies on standardisation of which elements?
- A.The telegrams and the useful data within them (data formats for switching, dimming, shutter, HVAC)
- B.The cable colours and connector shapes
- C.The power supply voltage and choke design
- D.The brand of ETS licence used
KNX System Arguments· KNX media & configuration modes· Medium
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Correct answer
A — The telegrams and the useful data within them (data formats for switching, dimming, shutter, HVAC)
Learning tip
Correct: standardised telegrams and standardised useful-data formats.
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Q07
KNX Secure provides two mechanisms. Which pair is correct?
- A.KNX RF Secure and KNX TP Secure
- B.KNX IP Secure (secure access via IP) and KNX Data Secure (secure communication between devices)
- C.KNX Firewall and KNX VPN
- D.KNX Password and KNX Token
KNX System Arguments· KNX media & configuration modes· Medium
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Correct answer
B — KNX IP Secure (secure access via IP) and KNX Data Secure (secure communication between devices)
Learning tip
Correct: KNX IP Secure (secure IP access) and KNX Data Secure (device-to-device).
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Q08
A KNX installation requires a central control unit (such as a PC) to coordinate the bus devices.
TrueFalse
KNX System Arguments· KNX media & configuration modes· Medium
Correct answer
False
Learning tip
False — every KNX bus device has its own microcontroller, so no central control unit is needed.
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Q09
The IP medium is the preferred choice when no cables can be installed.
TrueFalse
KNX System Arguments· KNX media & configuration modes· Medium
Correct answer
False
Learning tip
False — that is RF. IP is preferred for a fast backbone in large installations and for communication with mobile devices.
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Q10
In E-Mode, the application program is pre-installed in the device and configuration is done without a PC.
TrueFalse
KNX System Arguments· KNX media & configuration modes· Medium
Correct answer
True
Learning tip
Correct — E-Mode uses a central controller / push buttons, no PC, and the app program is pre-installed.
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Q11
Which licence do students receive upon acceptance into a Basic course at a certified KNX training centre?
- A.A time-limited, cloud-based ETS6 Lite licence
- B.A permanent ETS6 Professional licence
- C.An ETS Home licence
- D.No licence until they pass the exam
KNX System Arguments· KNX partnership & commercial· Medium
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Correct answer
A — A time-limited, cloud-based ETS6 Lite licence
Learning tip
Correct: a time-limited, cloud-based ETS6 Lite licence.
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Q12
What is the valid value range of the bus-device field in a KNX individual address?
- A.0 to 255
- B.0 to 15
- C.0 to 31
- D.1 to 255
System Overview· Individual & group addresses· Medium
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Correct answer
A — 0 to 255
Learning tip
Correct: The bus-device field of an individual address ranges from 0 to 255.
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Q13
How many bits make up the individual address within a KNX telegram?
- A.8 bits
- B.16 bits
- C.32 bits
- D.24 bits
System Overview· Individual & group addresses· Medium
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Correct answer
B — 16 bits
Learning tip
Correct: The individual address has a fixed structure of 16 bits.
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Q14
What is the primary purpose of the individual address?
- A.To carry everyday switching commands such as light on/off
- B.To link the group objects of several devices for one function
- C.To forward programming telegrams and new application/parameter data via ETS to the bus device
- D.To supply operating power to the bus device
System Overview· Individual & group addresses· Medium
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Correct answer
C — To forward programming telegrams and new application/parameter data via ETS to the bus device
Learning tip
Correct: The source states this is the primary goal of the individual address.
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Q15
Once commissioning (with all customisation and diagnostics) is complete, how is normal communication such as light on/off carried out?
- A.Exclusively via individual addresses
- B.Via the broadcast address 0/0/0
- C.Via both individual and group addresses equally
- D.Exclusively via group addresses
System Overview· Individual & group addresses· Medium
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Correct answer
D — Exclusively via group addresses
Learning tip
Correct: After commissioning, communication is done exclusively via group addresses.
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Q16
In the classic first-assignment procedure using the programming button (without a serial number), when can the individual address be downloaded?
- A.Only as long as the programming LED is lit
- B.At any time during normal operation
- C.Only after the device has been powered off
- D.Only via a group address telegram
System Overview· Individual & group addresses· Medium
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Correct answer
A — Only as long as the programming LED is lit
Learning tip
In the classic button-based assignment procedure, the programming LED identifies the device. ETS can also overwrite a known address without physically pressing the button, or assign an address by serial number on compatible devices. These exceptions do not allow arbitrary writing "at any time".
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Q17
What is the group address 0/0/0 reserved for?
- A.The first lighting circuit in the building
- B.Broadcast, required for assigning and establishing individual addresses
- C.Central switching of all actuators
- D.Indicating the programming LED state
System Overview· Individual & group addresses· Medium
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Correct answer
B — Broadcast, required for assigning and establishing individual addresses
Learning tip
Correct: 0/0/0 is reserved as the broadcast address, used when assigning individual addresses.
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Q18
Which three group address representations can be selected for an ETS project?
- A.1-level, 2-level and 3-level numeric
- B.Area/Line/Device, Main/Sub and free
- C.3-level (main/middle/sub), 2-level (main/sub) and a freely defined structure
- D.Decimal, hexadecimal and binary
System Overview· Individual & group addresses· Medium
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Correct answer
C — 3-level (main/middle/sub), 2-level (main/sub) and a freely defined structure
Learning tip
Correct: The source lists these three representation options.
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Q19
In the 3-level group address structure, what are the value ranges of main / middle / sub?
- A.Main 0-31, Middle 0-7, Sub 0-255
- B.Main 0-15, Middle 0-15, Sub 0-255
- C.Main 0-31, Middle 0-255, Sub 0-7
- D.Main 0-7, Middle 0-31, Sub 0-2047
System Overview· Individual & group addresses· Medium
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Correct answer
A — Main 0-31, Middle 0-7, Sub 0-255
Learning tip
Correct: The 3-level structure uses main 0-31, middle 0-7, sub 0-255.
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Q20
In the 2-level group address structure, what are the ranges of main / sub?
- A.Main 0-31, Sub 0-255
- B.Main 0-31, Sub 0-2047
- C.Main 0-15, Sub 0-2047
- D.Main 0-2047, Sub 0-31
System Overview· Individual & group addresses· Medium
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Correct answer
B — Main 0-31, Sub 0-2047
Learning tip
Correct: The 2-level structure uses main 0-31 and sub 0-2047.
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Q21
What is the value range of a freely structured (free) group address?
- A.0 to 65535
- B.1 to 32767
- C.1 to 65535
- D.0 to 2047
System Overview· Individual & group addresses· Medium
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Correct answer
C — 1 to 65535
Learning tip
Correct: The free structure allows values 1 to 65535.
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Q22
How many group addresses are available in total from ETS4 onwards?
- A.32767
- B.65536
- C.255
- D.65535
System Overview· Individual & group addresses· Medium
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Correct answer
D — 65535
Learning tip
Correct: From ETS4 onwards 65535 group addresses are available.
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Q23
Within a bus device, to what are group addresses assigned?
- A.To the group objects of the device
- B.To the individual address of the device
- C.To the programming LED
- D.To the choke of the power supply
System Overview· Individual & group addresses· Medium
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Correct answer
A — To the group objects of the device
Learning tip
Correct: Group addresses are assigned to the group objects of the respective bus devices.
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Q24
According to the three-level convention presented in this course, what does the main group represent?
- A.The functional domain (lighting, heating, ...)
- B.The floor number
- C.The individual load
- D.The area of the topology
System Overview· Individual & group addresses· Medium
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Correct answer
B — The floor number
Learning tip
Correct: In the common convention the main group is the floor number. This project convention is not imposed by the KNX protocol; other consistent organisations, including by function, are possible.
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Q25
In KNX TP, which logical state is represented by current being drawn (signal voltage present) on the line?
- A.Logical 0
- B.Logical 1
- C.Neither state draws current; both are coded purely by a voltage level
- D.Both 0 and 1 draw the same current
System Overview· Bus access & signal transmission· Medium
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Correct answer
A — Logical 0
Learning tip
Correct: During logical state 0 there is signal voltage and current is drawn on the line.
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Q26
If several KNX TP devices transmit at the same time, which logical state prevails on the bus?
- A.Logical 1, because 1 is the idle state
- B.Logical 0, because a 0 draws current and overrides a 1
- C.Whichever device began transmitting first
- D.Neither, because both telegrams are corrupted
System Overview· Bus access & signal transmission· Medium
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Correct answer
B — Logical 0, because a 0 draws current and overrides a 1
Learning tip
Correct: A 0 draws current on the line, so if any device sends a 0 the bus shows 0 and the 0 prevails.
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Q27
How is bus access organised in KNX TP?
- A.A central master polls each device in turn
- B.A token is passed between devices in a fixed order
- C.Decentralised: there is no central master/slave controller and each device accesses the bus itself
- D.The power supply assigns each device a fixed time slot
System Overview· Bus access & signal transmission· Medium
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Correct answer
C — Decentralised: there is no central master/slave controller and each device accesses the bus itself
Learning tip
Correct: KNX TP bus access is not controlled centrally by a master/slave scheme; devices access the bus on their own.
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Q28
What does the abbreviation CSMA/CA stand for in KNX TP bus access?
- A.Carrier Sense Multiple Access with Collision Detection
- B.Central Signal Management with Automatic arbitration
- C.Cyclic Slot Multiple Access with Contention Avoidance
- D.Carrier Sense Multiple Access with Collision Avoidance
System Overview· Bus access & signal transmission· Medium
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Correct answer
D — Carrier Sense Multiple Access with Collision Avoidance
Learning tip
Correct: CSMA/CA stands for Carrier Sense Multiple Access with Collision Avoidance.
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Q29
During transmission, when does a KNX TP bus device listen to the bus?
- A.While transmitting, as long as it is not itself sending a logical 0
- B.Only before it starts transmitting, never during
- C.Only after the whole telegram has been sent
- D.Never, because a transmitting device cannot receive at the same time
System Overview· Bus access & signal transmission· Medium
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Correct answer
A — While transmitting, as long as it is not itself sending a logical 0
Learning tip
Correct: Bus devices listen to the bus while transmitting, except when they are themselves sending a logical 0.
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Q30
After a KNX TP device stops transmitting because another device is sending a 0, what does it do next?
- A.It discards its telegram and never retries
- B.It immediately resends on top of the ongoing telegram
- C.It keeps listening until the current telegram ends, evaluates it, then tries to send its own telegram again
- D.It waits for a central master to grant it access again
System Overview· Bus access & signal transmission· Medium
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Correct answer
C — It keeps listening until the current telegram ends, evaluates it, then tries to send its own telegram again
Learning tip
Correct: The device that stopped continues to listen to the end of the telegram, evaluates it, and attempts to send again.
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Q31
What is the effect of CSMA/CA collision handling on data throughput in KNX TP?
- A.Throughput halves whenever two devices collide
- B.All colliding telegrams are lost and resent, lowering throughput
- C.Throughput drops to zero until a master resets the bus
- D.Throughput is not reduced, because the winning telegram completes without data loss
System Overview· Bus access & signal transmission· Medium
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Correct answer
D — Throughput is not reduced, because the winning telegram completes without data loss
Learning tip
Correct: Since one telegram continues uninterrupted and none is destroyed, data throughput is not reduced.
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Q32
A KNX TP device has a telegram ready, but a higher-priority telegram is currently on the bus. What happens?
- A.It waits until the higher-priority telegram has finished, then tries to send again
- B.It sends anyway, so the two telegrams mix on the bus
- C.The higher-priority telegram is aborted so the waiting device can send
- D.It discards its telegram permanently
System Overview· Bus access & signal transmission· Medium
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Correct answer
A — It waits until the higher-priority telegram has finished, then tries to send again
Learning tip
Correct: A device blocked by a higher-priority telegram waits for it to finish and then retries.
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Q33
In KNX symmetrical transmission, how are the two signal wires referenced to potential?
- A.One wire carries the signal and the other is connected to PE (ground)
- B.Neither wire is connected to ground/PE or to any fixed potential
- C.Both wires are tied to a fixed reference potential
- D.The black wire is grounded and the red wire carries the signal
System Overview· Bus access & signal transmission· Medium
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Correct answer
B — Neither wire is connected to ground/PE or to any fixed potential
Learning tip
Correct: The source states neither wire is connected to ground/PE nor to a fixed potential.
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Q34
What does a KNX TP bus device actually evaluate on the wire pair?
- A.The absolute voltage of each wire measured against ground
- B.The DC supply voltage level only
- C.Only the difference of the AC voltage between the two wires
- D.The sum of the voltages on both wires
System Overview· Bus access & signal transmission· Medium
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Correct answer
C — Only the difference of the AC voltage between the two wires
Learning tip
Correct: The bus device evaluates only the difference of the AC voltage between the two wires.
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Q35
Why does radiated external noise not disturb the KNX signal in symmetrical transmission?
- A.The device filters out all AC and keeps only the DC
- B.A shield connected to PE absorbs the noise before it reaches the wires
- C.The noise is always at a different frequency and is simply ignored
- D.Because the noise hits both wires with the same polarity, it does not change the voltage difference the device evaluates
System Overview· Bus access & signal transmission· Medium
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Correct answer
D — Because the noise hits both wires with the same polarity, it does not change the voltage difference the device evaluates
Learning tip
Correct: Radiated noise affects both wires with the same polarity and so has no effect on the evaluated difference.
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Q36
How are data and supply carried on the KNX TP bus pair?
- A.The AC data voltage is superimposed onto the DC supply voltage on the same pair
- B.Data uses one wire pair and the DC supply uses a separate pair
- C.The supply is an AC voltage and the data is a DC voltage
- D.Data and supply take turns in time on the same wires
System Overview· Bus access & signal transmission· Medium
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Correct answer
A — The AC data voltage is superimposed onto the DC supply voltage on the same pair
Learning tip
Correct: The AC data is superimposed onto the DC supply voltage on the same wire pair.
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Q37
Which component in a KNX bus device separates the DC supply voltage from the AC information (data) voltage?
- A.A shield connected to protective earth
- B.The transformer-IC
- C.A choke located inside each bus device
- D.The application interface
System Overview· Bus access & signal transmission· Medium
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Correct answer
B — The transformer-IC
Learning tip
Correct: The transformer-IC in the bus device separates the DC supply voltage from the AC information voltage.
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Q38
When does an S-mode KNX installation become ready for operation?
- A.As soon as the devices are mechanically mounted and the bus voltage is present.
- B.Immediately, because S-mode application programs are pre-installed at the factory.
- C.After the sensors and actuators have been downloaded with their application program via ETS.
- D.Once individual addresses are assigned, even if no application program is loaded yet.
System Overview· Configuration modes & group objects· Medium
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Correct answer
C — After the sensors and actuators have been downloaded with their application program via ETS.
Learning tip
Correct: the source states an S-mode installation is not ready until sensors and actuators are downloaded with the application program via ETS.
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Q39
Which of the following is NOT one of the ETS configuration steps for S-mode products?
- A.Assigning individual addresses to the devices.
- B.Selecting the appropriate application programs for the bus devices.
- C.Setting the parameters for the bus devices.
- D.Mechanically mounting the bus devices on the rail.
System Overview· Configuration modes & group objects· Medium
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Correct answer
D — Mechanically mounting the bus devices on the rail.
Learning tip
Correct: mounting the devices is done beforehand ('after mounting the devices'); it is not one of the ETS configuration steps, which are: assign individual addresses, select application programs, set parameters and assign group addresses.
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Q40
Using group addresses in ETS, which group objects may be linked together?
- A.Any two group objects, regardless of their size.
- B.Only group objects that have the same size.
- C.Only group objects located in the same bus device.
- D.Only group objects that are exactly 1 bit in size.
System Overview· Configuration modes & group objects· Medium
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Correct answer
B — Only group objects that have the same size.
Learning tip
Correct: the source states ETS only allows linking group objects that have the same size.
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Q41
Which set of components makes up a minimum KNX TP installation?
- A.A power supply, a line coupler, a sensor and an actuator
- B.Only a sensor and an actuator wired directly to 230 V
- C.A KNX power supply unit (30 V DC)/choke, one sensor, one actuator and the bus cable
- D.A power supply, a router, a gateway and several actuators
System Overview· Definition & minimal TP installation· Medium
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Correct answer
C — A KNX power supply unit (30 V DC)/choke, one sensor, one actuator and the bus cable
Learning tip
Correct: The source lists exactly these four elements for a minimum TP installation.
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Q42
What additional role can the spare wire pair of the KNX bus cable serve?
- A.Carrying 230 V mains to the actuators
- B.Providing ancillary (additional) power to bus devices
- C.Doubling the telegram transmission speed
- D.Acting as a protective earth
System Overview· Definition & minimal TP installation· Medium
▸
Correct answer
B — Providing ancillary (additional) power to bus devices
Learning tip
Correct: The source states the spare wire pair can provide ancillary power to bus devices.
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Q43
Apart from the 4-bit relative dimming object, which objects does the Dimming functional block consist of at least?
- A.Two shutter objects (DPT_Step 1.007 and DPT_UpDown 1.008).
- B.A temperature object (9.001) and a lux object (9.004).
- C.Only a single 1-bit switching object (DPT_Switch 1.001).
- D.A switching object (DPT_Switch 1.001) and a value object (DPT_Scaling 5.001).
System Overview· TP telegram data & datapoint types· Medium
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Correct answer
D — A switching object (DPT_Switch 1.001) and a value object (DPT_Scaling 5.001).
Learning tip
Correct: besides DPT_Control_Dimming (3.007), the dimming block has at least a switching object (1.001) and a value object (5.001).
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Q44
Which datapoint type does a typical dimming actuator support in addition to those supported by the dimming sensor?
- A.DPT_Scaling (5.001)
- B.DPT_Control_Dimming (3.007)
- C.DPT_Switch (1.001)
- D.DPT_UpDown (1.008)
System Overview· TP telegram data & datapoint types· Medium
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Correct answer
A — DPT_Scaling (5.001)
Learning tip
Correct: a typical dimming actuator additionally supports DPT_Scaling (5.001) for absolute brightness values.
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Q45
Which datapoint ID and name are correctly matched?
- A.1.001 - DPT_Step
- B.3.007 - DPT_Switch
- C.9.004 - DPT_Value_Temp
- D.5.001 - DPT_Scaling
System Overview· TP telegram data & datapoint types· Medium
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Correct answer
D — 5.001 - DPT_Scaling
Learning tip
Correct: 5.001 is DPT_Scaling, the 1-byte absolute value (scaling) object.
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Q46
What can occur if the maximum total bus length in a TP line segment is exceeded?
- A.The bus voltage rises above 30 V
- B.The choke is destroyed
- C.Nothing, because there is a built-in safety margin
- D.Irreproducible data transmission problems
System Overview· Power supply & cable lengths· Medium
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Correct answer
D — Irreproducible data transmission problems
Learning tip
Correct: The text states that irreproducible data transmission problems can occur.
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Q47
Why is a choke placed between the power supply and the bus line?
- A.To increase the bus voltage from 24 V to 30 V
- B.To stop the power supply's voltage regulator from correcting (cancelling) the AC information voltage
- C.To convert the 30 V DC into AC for the devices
- D.To protect the devices against short circuits
System Overview· Power supply & cable lengths· Medium
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Correct answer
B — To stop the power supply's voltage regulator from correcting (cancelling) the AC information voltage
Learning tip
Correct: Without the choke the regulator would try to correct the AC information voltage, causing a tug of war with the sending device.
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Q48
Which half of the AC voltage pulse is generated by the choke?
- A.The first (negative) half
- B.Both halves
- C.The second (positive) half
- D.Neither; the sending bus device generates the whole pulse
System Overview· Power supply & cable lengths· Medium
▸
Correct answer
C — The second (positive) half
Learning tip
Correct: The choke generates the second (positive) half of the pulse.
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Q49
Why may bus devices only be installed up to 350 m from the choke (power supply unit)?
- A.Because beyond 350 m the 30 V DC supply drops to zero
- B.Because collisions cannot be resolved beyond 350 m
- C.Because ETS cannot address devices further than 350 m away
- D.Because the choke plays a significant role in forming the equalization pulse
System Overview· Power supply & cable lengths· Medium
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Correct answer
D — Because the choke plays a significant role in forming the equalization pulse
Learning tip
Correct: The choke helps form the positive equalization pulse, so devices must stay within 350 m of it.
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Q50
Which effects make it necessary to limit the total cable length per line segment to 1000 m?
- A.Signal damping and edge-rounding by the cable capacity, plus a signal-level drop from the resistive load
- B.Overheating of the choke and the voltage regulator
- C.Loss of the 30 V DC supply beyond 1000 m
- D.ETS addressing limits
System Overview· Power supply & cable lengths· Medium
▸
Correct answer
A — Signal damping and edge-rounding by the cable capacity, plus a signal-level drop from the resistive load
Learning tip
Correct: These two effects degrade the signal, so the segment is limited to 1000 m.
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Q51
What does the maximum number of devices per TP line segment depend on?
- A.Always exactly 64 devices, regardless of consumption
- B.The total power consumption of the devices
- C.The total cable length only
- D.The number of power supply units only
System Overview· Power supply & cable lengths· Medium
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Correct answer
B — The total power consumption of the devices
Learning tip
Correct: The maximum number of devices per segment depends on their total power consumption.
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Q52
For a building planned and commissioned from 2019, what is the ideal maximum number of bus devices per floor?
- A.256
- B.64
- C.255
- D.128
KNX Topology· Building structure, backbone & interfaces· Medium
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Correct answer
A — 256
Learning tip
Correct: From 2019 an ideal installation has no more than 256 bus devices per floor.
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Q53
Which pairing of date range and ideal bus devices per floor is correct?
- A.Prior to 2018: 256 per floor; from 2019: 64 per floor.
- B.Prior to 2018: 64 per floor; from 2019: 256 per floor.
- C.Prior to 2018: 64 per floor; from 2019: 128 per floor.
- D.Prior to 2018: 255 per floor; from 2019: 255 per floor.
KNX Topology· Building structure, backbone & interfaces· Medium
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Correct answer
B — Prior to 2018: 64 per floor; from 2019: 256 per floor.
Learning tip
Correct: The ideal figures are 64 per floor prior to 2018 and 256 per floor from 2019.
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Q54
How is faster line-crossing communication achieved when adapting a KNX topology to IP?
- A.Every TP device is replaced by an IP device.
- B.The IP network takes the place of the main/backbone lines, replacing line- and backbone couplers with KNXnet/IP routers.
- C.The TP line speed is increased above 9,600 bit/s.
- D.Line couplers are removed entirely and no filtering is done.
KNX Topology· Building structure, backbone & interfaces· Medium
▸
Correct answer
B — The IP network takes the place of the main/backbone lines, replacing line- and backbone couplers with KNXnet/IP routers.
Learning tip
Correct: IP replaces the main/backbone line level and KNXnet/IP routers replace the line/backbone couplers.
View the full question page →
Q55
Using Gigabit switches, how much faster can data be transmitted for line-crossing communication compared with a TP main/backbone line?
- A.About 1,000 times faster.
- B.About 100 times faster.
- C.About 100,000 times faster.
- D.About 10 times faster.
KNX Topology· Building structure, backbone & interfaces· Medium
▸
Correct answer
C — About 100,000 times faster.
Learning tip
Correct: The source states data can be transmitted 100,000 times faster with Gigabit switches.
View the full question page →
Q56
Which IP communication method is commonly used by ETS for programming over IP?
- A.Routing.
- B.Multicast broadcasting only.
- C.A serial interface connection.
- D.Tunneling.
KNX Topology· Building structure, backbone & interfaces· Medium
▸
Correct answer
D — Tunneling.
Learning tip
Correct: Tunneling is the standardized method commonly used by ETS for programming over IP.
View the full question page →
Q57
What does a coupler's filter table contain?
- A.The individual addresses of all devices on the secondary line.
- B.Every group address used anywhere in the installation.
- C.The routing counter values for each telegram.
- D.The active line-crossing group addresses (linked to devices on both sides of the coupler).
KNX Topology· Couplers: function, block diagram & application· Medium
▸
Correct answer
D — The active line-crossing group addresses (linked to devices on both sides of the coupler).
Learning tip
Correct: the filter table contains the active line-crossing group addresses, i.e. all group addresses linked to bus devices on both sides of the coupler.
View the full question page →
Q58
Which telegrams does a line or backbone coupler forward across the lines it connects?
- A.Only line-crossing telegrams whose group address is in its filter table.
- B.All telegrams it receives, unchanged.
- C.Only telegrams sent to individual addresses.
- D.None - a coupler only galvanically isolates the lines.
KNX Topology· Couplers: function, block diagram & application· Medium
▸
Correct answer
A — Only line-crossing telegrams whose group address is in its filter table.
Learning tip
Correct: couplers route only line-crossing telegrams, i.e. those whose group address is in the filter table; each line works independently.
View the full question page →
Q59
How does a line repeater differ from a line coupler in the way it handles telegrams?
- A.The repeater filters telegrams using a larger filter table.
- B.The repeater has no filter table and passes on all telegrams.
- C.The repeater routes only individually addressed telegrams.
- D.The repeater blocks all telegrams to isolate the segment.
KNX Topology· Couplers: function, block diagram & application· Medium
▸
Correct answer
B — The repeater has no filter table and passes on all telegrams.
Learning tip
Correct: the line repeater has no filter table and therefore passes on all telegrams, unlike a coupler which forwards only line-crossing telegrams.
View the full question page →
Q60
What is the advantage of supplying a coupler from the primary line rather than the secondary line?
- A.It doubles the number of devices allowed on the secondary line.
- B.It removes the need for a choke on the secondary line.
- C.The coupler can report a power failure of the secondary line.
- D.It lets the coupler work without a controller.
KNX Topology· Couplers: function, block diagram & application· Medium
▸
Correct answer
C — The coupler can report a power failure of the secondary line.
Learning tip
Correct: if supplied by the primary line, the coupler can report a secondary line power failure.
View the full question page →
Q61
What determines whether a coupler acts as a backbone coupler, a line coupler or a line repeater?
- A.Three different hardware models are used, one per role.
- B.The number of devices connected to the secondary line.
- C.A hardware switch on the coupler set during installation.
- D.Its location and the assigned individual address.
KNX Topology· Couplers: function, block diagram & application· Medium
▸
Correct answer
D — Its location and the assigned individual address.
Learning tip
Correct: the couplers are identical devices whose task depends on the location and the corresponding assigned individual address.
View the full question page →
Q62
Between which two lines does a backbone coupler (BC) provide the connection?
- A.Between the backbone line and a main line.
- B.Between two secondary lines.
- C.Between a main line and a secondary line.
- D.Between a line segment and the next line segment.
KNX Topology· Couplers: function, block diagram & application· Medium
▸
Correct answer
A — Between the backbone line and a main line.
Learning tip
Correct: the backbone coupler BC provides the connection between the backbone line and the main line.
View the full question page →
Q63
A line coupler (LC) is used to connect which two lines?
- A.The backbone line and a main line.
- B.A main line and a secondary line.
- C.Two line segments of the same line.
- D.The backbone line and a secondary line directly.
KNX Topology· Couplers: function, block diagram & application· Medium
▸
Correct answer
B — A main line and a secondary line.
Learning tip
Correct: the line coupler LC connects the main line and a secondary line.
View the full question page →
Q64
By how many line segments can a line repeater extend a line, at most?
- A.1 line segment
- B.15 line segments
- C.3 line segments
- D.4 line segments
KNX Topology· Couplers: function, block diagram & application· Medium
▸
Correct answer
C — 3 line segments
Learning tip
Correct: a line repeater extends a line by a maximum of 3 line segments.
View the full question page →
Q65
What does a line coupler do with the data communication between the main line and its secondary line?
- A.It forwards all telegrams in both directions.
- B.It monitors the communication both ways and routes only telegrams whose group addresses are in its filter table.
- C.It blocks all traffic between the two lines.
- D.It converts individual addresses into group addresses.
KNX Topology· Couplers: function, block diagram & application· Medium
▸
Correct answer
B — It monitors the communication both ways and routes only telegrams whose group addresses are in its filter table.
Learning tip
Correct: the line coupler monitors data communication between the main line and the secondary line and vice versa, routing only telegrams whose group addresses are stored in its filter table.
View the full question page →
Q66
In an installation with several lines, how is power supplied to the lines?
- A.One central power supply feeds all lines through the couplers.
- B.Only the main line needs a power supply; secondary lines draw from it.
- C.Each line and each line segment has its own power supply unit and choke.
- D.A power supply is needed per area, shared by its lines.
KNX Topology· Couplers: function, block diagram & application· Medium
▸
Correct answer
C — Each line and each line segment has its own power supply unit and choke.
Learning tip
Correct: each line and each line segment must have its own power supply unit and choke.
View the full question page →
Q67
What does the value L = 0 address in a KNX individual address?
- A.The first bus device of the line.
- B.The backbone line of the installation.
- C.The main line of the respective area.
- D.The line coupler of the line.
KNX Topology· Individual address structure in the topology· Medium
▸
Correct answer
C — The main line of the respective area.
Learning tip
Correct: L = 0 addresses the main line of the respective area.
View the full question page →
Q68
A device carries the individual address 1.1.0. What does the device number 0 tell you?
- A.It is the line coupler of that line (x.y.0 addresses the line coupler).
- B.It is the first ordinary bus device on the line.
- C.It is an unloaded device still at its factory default.
- D.It is the backbone coupler of the area.
KNX Topology· Individual address structure in the topology· Medium
▸
Correct answer
A — It is the line coupler of that line (x.y.0 addresses the line coupler).
Learning tip
Correct: B = 0 addresses the line coupler in the respective line; 1.1.0 is the line coupler of line 1 in area 1.
View the full question page →
Q69
In which situation does the high bit rate of the Ethernet backbone NOT prevent problems?
- A.When the routing counter of a telegram reaches zero.
- B.Whenever a line has fewer than 240 devices.
- C.Only when RF segments are present in the installation.
- D.When telegrams are sent out simultaneously from all lines into one single line.
KNX Topology· KNXnet/IP routers & segment coupler· Medium
▸
Correct answer
D — When telegrams are sent out simultaneously from all lines into one single line.
Learning tip
Correct: the source says Ethernet's higher speed will not help when all lines send telegrams simultaneously into one single line.
View the full question page →
Q70
Before segment couplers, what was the maximum number of small TP islands that could be connected via an IP backbone (the 'hotel scenario')?
- A.240
- B.225
- C.256
- D.255
KNX Topology· KNXnet/IP routers & segment coupler· Medium
▸
Correct answer
A — 240
Learning tip
Correct: the source gives a maximum of 240 TP islands (225 + 15).
View the full question page →
Q71
Why were segment couplers needed for adding a few RF devices to a TP installation, especially an existing one?
- A.RF devices cannot coexist with TP devices under any circumstances.
- B.RF devices require their own area with its own backbone coupler.
- C.Previously the media coupler had to be installed in the main line, but a single-line installation (e.g. 1.1) has no main line - so a way to branch a TP line off for RF devices was needed.
- D.The routing counter must be reset for RF telegrams.
KNX Topology· KNXnet/IP routers & segment coupler· Medium
▸
Correct answer
C — Previously the media coupler had to be installed in the main line, but a single-line installation (e.g. 1.1) has no main line - so a way to branch a TP line off for RF devices was needed.
Learning tip
Correct: without a main line (as in a single line 1.1), the old media coupler had nowhere to go, so branching a TP line for RF devices became necessary.
View the full question page →
Q72
Which statement about filtering between the segments of a line is correct?
- A.TP line repeaters filter between segments, so segment couplers were unnecessary.
- B.Neither repeaters nor segment couplers can filter within a line.
- C.Filtering between segments only works over an IP backbone.
- D.Segment couplers introduce filtering between different segments of a line, which does not exist with TP line repeaters.
KNX Topology· KNXnet/IP routers & segment coupler· Medium
▸
Correct answer
D — Segment couplers introduce filtering between different segments of a line, which does not exist with TP line repeaters.
Learning tip
Correct: providing inter-segment filtering - absent in TP repeaters - was one reason for segment couplers.
View the full question page →
Q73
Into how many subsegments (besides the main segment) can TP line repeaters physically subdivide a line?
- A.Up to three
- B.Any number
- C.Up to seven
- D.Exactly one
KNX Topology· KNXnet/IP routers & segment coupler· Medium
▸
Correct answer
A — Up to three
Learning tip
Correct: TP repeaters allow a main segment plus up to three subsegments.
View the full question page →
Q74
What is a limitation of TP line repeaters compared with segment couplers?
- A.They filter group addresses but not individual addresses.
- B.They are unaware which device address is in which subsegment and have no filter table, so they forward all traffic.
- C.They can only be used on RF media.
- D.They limit a line to 240 devices.
KNX Topology· KNXnet/IP routers & segment coupler· Medium
▸
Correct answer
B — They are unaware which device address is in which subsegment and have no filter table, so they forward all traffic.
Learning tip
Correct: repeaters cannot tell where an address lives and have no filter table, so every telegram reaches every segment.
View the full question page →
Q75
How many main segments does a line have when using segment couplers?
- A.Up to three
- B.Any number
- C.One per subsegment
- D.Exactly one
KNX Topology· KNXnet/IP routers & segment coupler· Medium
▸
Correct answer
D — Exactly one
Learning tip
Correct: each line has exactly one main segment (plus any number of subsegments).
View the full question page →
Q76
Device 1.1.44 is an RF device sitting in an RF subsegment behind a TP-RF segment coupler on a TP main segment. What does this show?
- A.A subsegment may use a different medium (RF) than its main segment (TP).
- B.Individual addresses encode the transmission medium.
- C.An RF device must always have device address 0.
- D.The main segment must also be converted to RF.
KNX Topology· KNXnet/IP routers & segment coupler· Medium
▸
Correct answer
A — A subsegment may use a different medium (RF) than its main segment (TP).
Learning tip
Correct: subsegments can be a different medium type; an RF subsegment can be coupled to a TP main segment.
View the full question page →
Q77
Regardless of how many subsegments it contains, the maximum number of devices in a single line (including all couplers) is:
- A.240
- B.255
- C.225
- D.256
KNX Topology· KNXnet/IP routers & segment coupler· Medium
▸
Correct answer
D — 256
Learning tip
Correct: a line may hold no more than 256 devices in total, including all couplers.
View the full question page →
Q78
A telegram is transmitted on a line. Which devices execute the command it carries?
- A.Every device on the line, because all of them receive the telegram.
- B.Only the line coupler of that line.
- C.Only the device that sent the telegram.
- D.Only the devices whose parameters contain the matching group address.
KNX Topology· Telegram routing & routing counter· Medium
▸
Correct answer
D — Only the devices whose parameters contain the matching group address.
Learning tip
Correct: All devices listen in, but only those with the same group address as the telegram execute the command.
View the full question page →
Q79
What must happen for a telegram to reach a device located on a different line of the same area?
- A.It travels directly from one line to the other without any coupler.
- B.It must be transmitted via the main line, routed by the line couplers of both lines.
- C.It must always be routed over the backbone line.
- D.It must be resent manually because lines cannot exchange telegrams.
KNX Topology· Telegram routing & routing counter· Medium
▸
Correct answer
B — It must be transmitted via the main line, routed by the line couplers of both lines.
Learning tip
Correct: A line-crossing telegram travels up to the main line and back down, routed by the line couplers of the source and destination lines.
View the full question page →
Q80
Why does line coupler LC 2 route the sensor's group telegram 0/2/11 onto the main line?
- A.A line coupler forwards every telegram it receives to the main line.
- B.Because the routing counter had already reached 0.
- C.Its parameterisation (filter table) shows that devices outside line 2 respond to that group address.
- D.Because only line repeaters, not couplers, can forward telegrams.
KNX Topology· Telegram routing & routing counter· Medium
▸
Correct answer
C — Its parameterisation (filter table) shows that devices outside line 2 respond to that group address.
Learning tip
Correct: LC 2 forwards 0/2/11 because its filter table shows external devices need it.
View the full question page →
Q81
How can a device address bus devices located in a different area?
- A.Via the backbone line, which interconnects the areas.
- B.Via the main line only, without the backbone line.
- C.Directly, because all areas share one common line.
- D.It cannot; devices in different areas can never communicate.
KNX Topology· Telegram routing & routing counter· Medium
▸
Correct answer
A — Via the backbone line, which interconnects the areas.
Learning tip
Correct: An area-crossing telegram uses the backbone line to move between areas.
View the full question page →
Q82
Which devices decrement the routing counter of a telegram?
- A.Only backbone couplers, never line couplers or repeaters.
- B.Only the sending device, once, before transmission.
- C.The receiving actuator when it executes the command.
- D.Every line-/backbone coupler and every line repeater that passes the telegram on.
KNX Topology· Telegram routing & routing counter· Medium
▸
Correct answer
D — Every line-/backbone coupler and every line repeater that passes the telegram on.
Learning tip
Correct: Line couplers, backbone couplers and line repeaters each decrement the routing counter when forwarding.
View the full question page →
Q83
Up to what cable length can 256 devices sit in one line without needing any line repeater?
- A.4000 m
- B.100 m
- C.1000 m
- D.700 m
KNX Topology· Line segment, line, area & network structure· Medium
▸
Correct answer
C — 1000 m
Learning tip
One repeater links two segments and adds one segment. Up to three repeaters allow four segments in total, each limited to 1000 m with suitable power supply. Distinguish TP-64 from TP-256: capacity depends on product compatibility and available current. 1000 m is the cable-length limit per segment, not proof of compliance; also check distances and load.
View the full question page →
Q84
With the maximum of 3 line repeaters, what is the maximum TOTAL cable length of one line?
- A.1000 m
- B.3000 m
- C.4000 km
- D.4000 m
KNX Topology· Line segment, line, area & network structure· Medium
▸
Correct answer
D — 4000 m
Learning tip
Correct: four 1000 m segments joined by 3 repeaters give a maximum total of 4000 m.
View the full question page →
Q85
What determines whether one and the same coupler hardware acts as a line repeater, a line coupler or a backbone coupler?
- A.A physically different model for each role
- B.The loaded application program and its individual address
- C.Its physical position in the distribution board
- D.The colour of its bus terminal
KNX Topology· Line segment, line, area & network structure· Medium
▸
Correct answer
B — The loaded application program and its individual address
Learning tip
Correct: the source states the loaded application and the individual address determine the role.
View the full question page →
Q86
Including the mounted line-/backbone couplers, how many bus devices can be topologically addressed on a main line?
- A.255
- B.15
- C.16
- D.256
KNX Topology· Line segment, line, area & network structure· Medium
▸
Correct answer
D — 256
Learning tip
Correct: up to 256 bus devices, including the mounted couplers, can be addressed on the main line.
View the full question page →
Q87
What is the maximum number of couplers (line- or backbone couplers) that a main line may carry?
- A.16
- B.256
- C.15
- D.4
KNX Topology· Line segment, line, area & network structure· Medium
▸
Correct answer
A — 16
Learning tip
Correct: the source states a maximum of 16 couplers on the main line.
View the full question page →
Q88
Approximately how many devices can be installed in one complete area?
- A.More than 250,000
- B.More than 4,000
- C.More than 61,000
- D.Exactly 256
KNX Topology· Line segment, line, area & network structure· Medium
▸
Correct answer
B — More than 4,000
Learning tip
Correct: the source states more than 4,000 devices can be installed in one area.
View the full question page →
Q89
The spare wire pair (white/yellow) of the KNX bus cable may be used for which of the following?
- A.A second KNX TP data signal
- B.A DC SELV supply, or left with no connection at all
- C.Voice communication
- D.A 230 V AC mains supply
KNX Installation· Bus cable types, installation & distribution boards· Medium
▸
Correct answer
B — A DC SELV supply, or left with no connection at all
Learning tip
Correct: Permitted uses are no connection at all or a DC SELV supply.
View the full question page →
Q90
How should the shielding of KNX bus cables be treated regarding the equipotential bonding bar?
- A.It must be bonded to the equipotential bar at every device
- B.It must be earthed at the power supply only
- C.It must be connected to the protective earth of the mains
- D.It may not be connected to the equipotential bonding bar
KNX Installation· Bus cable types, installation & distribution boards· Medium
▸
Correct answer
D — It may not be connected to the equipotential bonding bar
Learning tip
Correct: The shielding of the bus cables may not be connected to the equipotential bonding bar.
View the full question page →
Q91
On which DIN rails may KNX TP DIN-rail mounted devices be installed in a distribution board?
- A.Standardized EN 50022 35x7.5 mm DIN rails
- B.Only proprietary KNX rails supplied by the manufacturer
- C.EN 50090 15x5 mm rails
- D.Only earthed metal rails used as the SELV return
KNX Installation· Bus cable types, installation & distribution boards· Medium
▸
Correct answer
A — Standardized EN 50022 35x7.5 mm DIN rails
Learning tip
Correct: Any commercial board with EN 50022 35x7.5 mm DIN rails may be used.
View the full question page →
Q92
In a KNX TP line, what is the maximum permitted distance between the power supply unit and a bus device?
- A.700 m
- B.1000 m
- C.350 m
- D.As specified by the manufacturer
KNX Installation· Checking the installation· Medium
▸
Correct answer
C — 350 m
Learning tip
Correct: The distance between the power supply unit and a bus device may not exceed 350 m.
View the full question page →
Q93
At what test voltage should the insulation resistance of the bus cable be measured?
- A.250 V DC
- B.230 V DC
- C.500 V DC
- D.21 V DC
KNX Installation· Checking the installation· Medium
▸
Correct answer
A — 250 V DC
Learning tip
Correct: The insulation resistance measurement should be carried out at 250 V DC.
View the full question page →
Q94
Why should overvoltage protectors be removed before measuring the insulation resistance of the bus cable?
- A.Because overvoltage protectors are only fitted on mains cables, never on bus cables.
- B.So the measurement is not influenced and the overvoltage protector is not damaged.
- C.To raise the test voltage above 250 V DC.
- D.Because the protectors must be replaced after every insulation test.
KNX Installation· Checking the installation· Medium
▸
Correct answer
B — So the measurement is not influenced and the overvoltage protector is not damaged.
Learning tip
Correct: Overvoltage protectors should always be removed before the test so that the measurement is not influenced and the protector is not damaged.
View the full question page →
Q95
What is the minimum bus voltage that must be measured at the end of each bus cable?
- A.24 V DC
- B.29 V DC
- C.20 V DC
- D.21 V DC
KNX Installation· Checking the installation· Medium
▸
Correct answer
D — 21 V DC
Learning tip
Correct: The bus voltage at each bus cable end should be at least 21 V DC.
View the full question page →
Q96
When the ETS project is handed over, the customer's signature confirms agreement with which of the following?
- A.Only the total price of the installation.
- B.All the realized functions, and that the installer's warranty expires with any change to the realized KNX installation.
- C.That the installer stays liable for any future changes made by others.
- D.That no project documentation needs to be provided.
KNX Installation· Checking the installation· Medium
▸
Correct answer
B — All the realized functions, and that the installer's warranty expires with any change to the realized KNX installation.
Learning tip
Correct: With the signature the customer agrees to all realized functions and that the installer's warranty expires with any change to the installation.
View the full question page →
Q97
In the sequence for checking a KNX installation, which check is carried out immediately after checking the polarity of all bus devices?
- A.Measuring the insulation resistance of the bus cables
- B.The visual check of the bus cable-end marking
- C.Measuring the bus voltage at each bus cable end
- D.Recording the test results
KNX Installation· Checking the installation· Medium
▸
Correct answer
C — Measuring the bus voltage at each bus cable end
Learning tip
Correct: The polarity check is followed by measuring the bus voltage (minimum 21 V) at each bus cable end.
View the full question page →
Q98
In a common installation box with a partition, what clearance and creepage distance does the source require between mains and bus?
- A.2.5 mm.
- B.8 mm.
- C.5.5 mm.
- D.0.5 mm.
KNX Installation· Wall boxes, flush-mounted devices & TP bus connector· Medium
▸
Correct answer
C — 5.5 mm.
Learning tip
Correct: the source requires 5.5 mm clearance and creepage distances.
View the full question page →
Q99
For the WAGO 243-211 connector: On the standardized KNX TP bus connector, which statement about the two parts is correct?
- A.The plus part is red and the minus part is black.
- B.The plus part is red and the minus part is dark grey.
- C.The plus part is black and the minus part is red.
- D.Both parts are green, matching the bus cable sheath.
KNX Installation· Wall boxes, flush-mounted devices & TP bus connector· Medium
▸
Correct answer
B — The plus part is red and the minus part is dark grey.
Learning tip
In the course, the connector has a red positive part and a dark-grey negative part, as on the WAGO 243-211. Other manufacturers, including ABB for XS/S 1.1, describe the connection as red/black. This naming difference is not a polarity difference: check +/− markings and the product manual instead of claiming that black always means only the cable conductor.
View the full question page →
Q100
How many bus wires can be connected to each part of the standardized TP bus connector?
- A.Up to 8 wires.
- B.Up to 2 wires.
- C.Exactly 1 wire.
- D.Up to 4 wires (6 mm stripped).
KNX Installation· Wall boxes, flush-mounted devices & TP bus connector· Medium
▸
Correct answer
D — Up to 4 wires (6 mm stripped).
Learning tip
Correct: up to 4 bus wires, stripped to 6 mm, fit each screwless part.
View the full question page →
Q101
What does 'primary protection' mean in the KNX lightning-protection context?
- A.Fitting an overvoltage protector directly at each bus device.
- B.Connecting active conductors indirectly to the equipotential bonding bar via lightning current arresters.
- C.The basic 2 kV immunity built into every bus device.
- D.The reverse-polarity keying of the TP bus connector.
KNX Installation· Lightning, overvoltage, loops & immunity· Medium
▸
Correct answer
B — Connecting active conductors indirectly to the equipotential bonding bar via lightning current arresters.
Learning tip
Correct: this indirect connection of active conductors through lightning current arresters is primary protection.
View the full question page →
Q102
For primary protection of the 230/400 V AC mains, what minimum nominal discharge current (10/350 us) is required per conductor?
- A.2.5 kA.
- B.5 kA.
- C.12.5 kA.
- D.25 kA.
KNX Installation· Lightning, overvoltage, loops & immunity· Medium
▸
Correct answer
C — 12.5 kA.
Learning tip
Correct: at least 12.5 kA (10/350 us) per conductor is required for the mains.
View the full question page →
Q103
For primary protection of the KNX bus line, what minimum nominal discharge current (10/350 us) per conductor is required?
- A.5 kA.
- B.12.5 kA.
- C.0.25 kA.
- D.2.5 kA.
KNX Installation· Lightning, overvoltage, loops & immunity· Medium
▸
Correct answer
D — 2.5 kA.
Learning tip
Correct: at least 2.5 kA (10/350 us) per conductor is required for the bus line.
View the full question page →
Q104
How does loop area relate to lightning-induced surges in a KNX installation?
- A.The larger the loop area, the smaller the surge.
- B.Loop area has no effect on surge magnitude.
- C.Only loops smaller than 1 m2 generate surges.
- D.The larger the loop area, the larger the expected peak surge.
KNX Installation· Lightning, overvoltage, loops & immunity· Medium
▸
Correct answer
D — The larger the loop area, the larger the expected peak surge.
Learning tip
Correct: the source states peak surge grows with loop area.
View the full question page →
Q105
To what surge voltage (core to earth) is the basic immunity of bus devices tested (IEC 63044-3)?
- A.4 kV.
- B.2 kV.
- C.600 V.
- D.350 V.
KNX Installation· Lightning, overvoltage, loops & immunity· Medium
▸
Correct answer
B — 2 kV.
Learning tip
Correct: basic immunity is tested with a 2 kV surge core to earth.
View the full question page →
Q106
Which situation is NOT listed by the source as a cause of more significant interference on the bus?
- A.Installing bus devices in loops.
- B.Running bus and high-power mains in parallel over a long distance.
- C.Using a certified twisted-pair bus cable of the correct colour.
- D.Bus devices connected to metal walls or central-heating pipes.
KNX Installation· Lightning, overvoltage, loops & immunity· Medium
▸
Correct answer
C — Using a certified twisted-pair bus cable of the correct colour.
Learning tip
Correct: cable certification/colour is not listed as a cause of interference.
View the full question page →
Q107
What does the source recommend for bus devices installed on cable ends?
- A.No extra measures, because basic immunity is always sufficient.
- B.Primary protection only, via a lightning current arrester.
- C.Removal of the terminating bus connector.
- D.Additional secondary protection (an overvoltage protector).
KNX Installation· Lightning, overvoltage, loops & immunity· Medium
▸
Correct answer
D — Additional secondary protection (an overvoltage protector).
Learning tip
Correct: additional secondary protection should be provided for bus devices on cable ends.
View the full question page →
Q108
How is the overvoltage protector with KNX bus connector design classified, and how does it differ from primary protection?
- A.It is secondary protection at the devices; primary protection uses lightning current arresters on active conductors.
- B.It is just the bus device's own 2 kV basic immunity.
- C.It is primary protection; secondary protection is the equipotential bonding bar.
- D.It is the same thing as a lightning current arrester.
KNX Installation· Lightning, overvoltage, loops & immunity· Medium
▸
Correct answer
A — It is secondary protection at the devices; primary protection uses lightning current arresters on active conductors.
Learning tip
Correct: the overvoltage protector is secondary protection, distinct from the primary lightning current arresters.
View the full question page →
Q109
What minimum nominal discharge current (and impulse shape) must the secondary overvoltage protector provide?
- A.At least 2.5 kA (10/350 us).
- B.At least 5 kA (8/20 us).
- C.At least 12.5 kA (10/350 us).
- D.At least 350 A (8/20 us).
KNX Installation· Lightning, overvoltage, loops & immunity· Medium
▸
Correct answer
B — At least 5 kA (8/20 us).
Learning tip
Correct: the overvoltage protector must provide at least 5 kA (8/20 us).
View the full question page →
Q110
How is the overvoltage protector connected, and can it branch the bus cable?
- A.Only by cutting the bus cable and hard-soldering it in line.
- B.It is the normal way to branch the bus cable into three directions.
- C.Via a conventional bus connector or directly to a bus device; it cannot branch the bus cable.
- D.Only through the 230 V mains terminals.
KNX Installation· Lightning, overvoltage, loops & immunity· Medium
▸
Correct answer
C — Via a conventional bus connector or directly to a bus device; it cannot branch the bus cable.
Learning tip
Correct: it connects with a bus connector or directly to a device, and cannot be used to branch the bus.
View the full question page →
Q111
For at least how long can a KNX power supply unit bridge a short interruption of the mains?
- A.1 s
- B.10 ms
- C.100 ms
- D.100 microseconds
KNX Installation· Power supply units, two-line & distributed supply· Medium
▸
Correct answer
C — 100 ms
Learning tip
Correct: The PSU can bridge short power gaps of a minimum of 100 ms.
View the full question page →
Q112
Why is a KNX TP power supply unit resistant to short circuits?
- A.Because it has integrated voltage and current control
- B.Because each bus device has its own fuse
- C.Because the bus is a SELV network
- D.Because it operates from the 230 V mains
KNX Installation· Power supply units, two-line & distributed supply· Medium
▸
Correct answer
A — Because it has integrated voltage and current control
Learning tip
Correct: The integrated voltage and current control makes the PSU resistant to short circuits.
View the full question page →
Q113
Which set of output currents corresponds to available centralized KNX TP power supply units?
- A.100, 200 and 400 mA
- B.160, 320, 640 and 1280 mA
- C.1, 2 and 4 A
- D.25, 40 and 80 mA
KNX Installation· Power supply units, two-line & distributed supply· Medium
▸
Correct answer
B — 160, 320, 640 and 1280 mA
Learning tip
Correct: The source lists these as available centralized PSU output currents.
View the full question page →
Q114
Which statement about the choke in KNX TP power supplies is correct?
- A.Every PSU always requires a separate external choke
- B.A choke is only needed on the 230 V mains side
- C.Some PSU types have an integrated choke; others need an additional external choke
- D.Chokes are never used in KNX TP installations
KNX Installation· Power supply units, two-line & distributed supply· Medium
▸
Correct answer
C — Some PSU types have an integrated choke; others need an additional external choke
Learning tip
Correct: The source states exactly this.
View the full question page →
Q115
What determines how many devices can be installed in a KNX TP line?
- A.The type of PSU used and the individual power consumption of the devices
- B.Exactly 64 devices, regardless of the PSU
- C.The colour of the bus connector
- D.Only the physical length of the bus cable
KNX Installation· Power supply units, two-line & distributed supply· Medium
▸
Correct answer
A — The type of PSU used and the individual power consumption of the devices
Learning tip
Correct: The source states the device count depends on the PSU type and each device's consumption.
View the full question page →
Q116
On a KNX power supply unit, what does a YELLOW LED indicate?
- A.The unit is overloaded, possibly due to a short circuit
- B.The 230 V mains supply has failed
- C.The power supply is active and within its normal operating range
- D.An external voltage higher than 30 V has been applied to the bus side
KNX Installation· Power supply units, two-line & distributed supply· Medium
▸
Correct answer
D — An external voltage higher than 30 V has been applied to the bus side
Learning tip
Correct: Yellow indicates an external voltage above 30 V on the bus side.
View the full question page →
Q117
Under what condition can a single power supply unit feed two lines?
- A.When additional current is needed, depending on the load
- B.Always – every PSU feeds exactly two lines
- C.Only if both lines together have fewer than 21 devices
- D.Never – one PSU can only ever feed one line
KNX Installation· Power supply units, two-line & distributed supply· Medium
▸
Correct answer
A — When additional current is needed, depending on the load
Learning tip
Correct: The source allows one PSU to feed two lines if extra current is needed and the load permits.
View the full question page →
Q118
In a distributed power supply, how is the bus powered?
- A.By connecting the 230 V mains directly to the bus
- B.By batteries fitted inside every bus device
- C.By several devices on the line, each containing a Decentralized Power Supply Unit (DPSU) with an integrated choke module
- D.By a single large centralized PSU only
KNX Installation· Power supply units, two-line & distributed supply· Medium
▸
Correct answer
C — By several devices on the line, each containing a Decentralized Power Supply Unit (DPSU) with an integrated choke module
Learning tip
Correct: The source describes the bus being powered by devices each containing a DPSU with an integrated choke module.
View the full question page →
Q119
How many DPSUs may be mounted in one single bus line (even if it consists of segments)?
- A.Up to 8
- B.Up to 2
- C.Up to 16
- D.Up to 64
KNX Installation· Power supply units, two-line & distributed supply· Medium
▸
Correct answer
A — Up to 8
Learning tip
Correct: Up to 8 DPSUs may be used; more than eight can negatively affect communication.
View the full question page →
Q120
What is the permitted voltage range in a SELV network?
- A.120 V for AC and 50 V for DC
- B.25 V for AC and 60 V for DC
- C.50 V for AC and 120 V for DC
- D.30 V for AC and 30 V for DC
KNX Installation· SELV networks & insulation· Medium
▸
Correct answer
C — 50 V for AC and 120 V for DC
Learning tip
Correct: The text lists 50 V for alternating current and 120 V for direct current.
View the full question page →
Q121
Below which voltages is NO special protection against direct contact required?
- A.50 V AC or 120 V DC
- B.60 V AC or 25 V DC
- C.30 V AC or 30 V DC
- D.25 V AC or 60 V DC
KNX Installation· SELV networks & insulation· Medium
▸
Correct answer
D — 25 V AC or 60 V DC
Learning tip
Correct: These are the limits stated for omitting direct-contact protection.
View the full question page →
Q122
How must a SELV network be treated with respect to earth?
- A.It may not be earthed and is isolated from earth and protective earth conductors
- B.It must be solidly earthed at the power supply
- C.It must be connected to the protective earth of the mains
- D.It must be earthed only in wet rooms
KNX Installation· SELV networks & insulation· Medium
▸
Correct answer
A — It may not be earthed and is isolated from earth and protective earth conductors
Learning tip
Correct: SELV must not be earthed and stays isolated from earth and PE conductors.
View the full question page →
Q123
What generates the SELV voltage for the KNX TP bus?
- A.A direct tap off one mains phase
- B.The earthing system of the building
- C.A power supply with secure mains separation
- D.A battery inside each bus device
KNX Installation· SELV networks & insulation· Medium
▸
Correct answer
C — A power supply with secure mains separation
Learning tip
Correct: The documentation states a power supply with secure mains separation generates the SELV voltage.
View the full question page →
Q124
From an electronics point of view, which two elements are integrated together to form a regular bus coupling unit (BCU)?
- A.The application module and the application program
- B.The transceiver and the microcontroller
- C.The transceiver and the digital-analog converter
- D.The programming button and the programming LED
KNX Bus Devices· Bus device components & function· Medium
▸
Correct answer
B — The transceiver and the microcontroller
Learning tip
Correct: The text says the transceiver and microcontroller are integrated in a regular BCU whose electronics cannot be separated.
View the full question page →
Q125
What are the two functions of the Physical External Interface (PEI) between a separated application module and bus coupling unit?
- A.Assigning the individual address and storing the application program
- B.Connecting the device to the KNX bus and supplying the full mains voltage
- C.Exchanging messages between the two parts and providing limited power to the application module
- D.Converting digital signals to analog and amplifying telegrams
KNX Bus Devices· Bus device components & function· Medium
▸
Correct answer
C — Exchanging messages between the two parts and providing limited power to the application module
Learning tip
Correct: The text lists exactly these two functions of the PEI.
View the full question page →
Q126
When a bus coupling unit and an application module are bought as separate components, what does the KNX documentation require regarding their origin?
- A.They may be freely combined from any KNX-certified manufacturers
- B.They only need to share the same medium (TP or RF)
- C.The BCU may be any brand but the AM must be KNX Association branded
- D.They must always be sourced from the same manufacturer
KNX Bus Devices· Bus device components & function· Medium
▸
Correct answer
D — They must always be sourced from the same manufacturer
Learning tip
Correct: The text states the BCU and AM must always be sourced from the same manufacturer.
View the full question page →
Q127
How are the bus coupling unit and application module usually arranged in a DIN rail-mounted KNX device?
- A.Inseparably connected together in one housing
- B.Always separated and joined through an external PEI
- C.As two DIN modules from different manufacturers
- D.Connected only by the KNX bus cable
KNX Bus Devices· Bus device components & function· Medium
▸
Correct answer
A — Inseparably connected together in one housing
Learning tip
Correct: The text states DIN rail-mounted devices usually integrate the BCU and AM inseparably in one housing.
View the full question page →
Q128
When a sensor's application module and bus coupling unit are physically separated (mainly with flush-mounted sensors), how are they connected?
- A.Only through the standardized KNX bus connector
- B.Through a standardized or manufacturer-specific Physical External Interface (PEI)
- C.Wirelessly via KNX-RF
- D.By soldering the application program onto the BCU
KNX Bus Devices· Bus device components & function· Medium
▸
Correct answer
B — Through a standardized or manufacturer-specific Physical External Interface (PEI)
Learning tip
Correct: The text says the application module can be connected to the BCU via a standardized or manufacturer-specific PEI.
View the full question page →
Q129
Inside an integrated KNX product, what is the role of the electronic circuit called the 'transceiver'?
- A.It runs the operating software and the application program
- B.It executes the application function such as switching a load
- C.It takes care of coupling to the medium and is responsible for sending and receiving telegrams
- D.It stores the individual address and group addresses
KNX Bus Devices· Bus device components & function· Medium
▸
Correct answer
C — It takes care of coupling to the medium and is responsible for sending and receiving telegrams
Learning tip
Correct: The text defines the transceiver as the circuit handling the coupling function to the medium, responsible for sending and receiving telegrams.
View the full question page →
Q130
Why is KNX described as a decentralized system that needs no central supervising unit?
- A.Because a central computer continuously supervises all devices
- B.Because all telegrams are routed through a mandatory master controller
- C.Because the power supply stores the application program for every device
- D.Because each bus device has its own intelligence from an integrated operating system and program memory
KNX Bus Devices· Bus device components & function· Medium
▸
Correct answer
D — Because each bus device has its own intelligence from an integrated operating system and program memory
Learning tip
Correct: The text says each device's own intelligence is why KNX is decentralized and needs no central unit.
View the full question page →
Q131
How is a TP (Twisted Pair) device usually connected to the KNX bus?
- A.Via the standardized bus connector, colour-coded dark grey/red
- B.Via a Physical External Interface (PEI)
- C.Via a mains plug at 230 V
- D.Via a white/yellow bus connector
KNX Bus Devices· Bus device components & function· Medium
▸
Correct answer
A — Via the standardized bus connector, colour-coded dark grey/red
Learning tip
Correct: The text says TP devices connect to the bus mostly via the standardized bus connector (dark grey/red).
View the full question page →
Q132
What is the purpose of putting a KNX device into programming mode with its programming button?
- A.To switch the connected electric load on or off
- B.To provide power to the application module
- C.To allow assignment of the device's individual address
- D.To couple the device to the bus medium
KNX Bus Devices· Bus device components & function· Medium
▸
Correct answer
C — To allow assignment of the device's individual address
Learning tip
Correct: The text equates programming mode with assignment of the individual address.
View the full question page →
Q133
For which two media are KNX bus coupling units currently available?
- A.Twisted Pair and Powerline
- B.Ethernet (KNXnet/IP) and RF
- C.RF and Powerline
- D.Twisted Pair (SELV) and RF (KNX-RF)
KNX Bus Devices· Bus device components & function· Medium
▸
Correct answer
D — Twisted Pair (SELV) and RF (KNX-RF)
Learning tip
Correct: The text says BCUs are available for two media, Twisted Pair (SELV) and RF (KNX-RF).
View the full question page →
Q134
Why is it rare nowadays to have a device with pure sensor or pure actuator functionality?
- A.Because controllers have replaced all sensors and actuators
- B.Because, for example, a push button with LED status display also has an actuator function and an actuator with status information also has a sensor function
- C.Because every device must contain a digital-analog converter
- D.Because pure sensors are not allowed on Twisted Pair
KNX Bus Devices· Bus device components & function· Medium
▸
Correct answer
B — Because, for example, a push button with LED status display also has an actuator function and an actuator with status information also has a sensor function
Learning tip
Correct: The text gives exactly these examples of devices combining both roles.
View the full question page →
Q135
Which sequence correctly describes how a KNX sensor works?
- A.The BCU receives a telegram from the bus and the application module switches a load
- B.The application module sends telegrams directly onto the bus without the BCU
- C.The application module reports its inputs to the BCU, which codes the data and sends it on the bus
- D.The controller reads the inputs and the sensor regulates the actuators
KNX Bus Devices· Bus device components & function· Medium
▸
Correct answer
C — The application module reports its inputs to the BCU, which codes the data and sends it on the bus
Learning tip
Correct: This is the sensor data path stated in the text.
View the full question page →
Q136
What does the bus coupling unit of an actuator do when a telegram arrives from the bus?
- A.It codes the state of its inputs and sends a new telegram on the bus
- B.It regulates the interaction between other sensors and actuators
- C.It assigns itself an individual address
- D.It decodes the telegram and passes the information to the application module, which executes the command
KNX Bus Devices· Bus device components & function· Medium
▸
Correct answer
D — It decodes the telegram and passes the information to the application module, which executes the command
Learning tip
Correct: The text says the actuator's BCU receives and decodes telegrams and passes them to the AM, which executes the command.
View the full question page →
Q137
Which statement correctly characterises a KNX controller?
- A.It regulates the interaction between sensors and actuators and has no physical inputs or outputs
- B.It detects physical variables and reports its inputs on the bus
- C.It receives telegrams and switches an electric load
- D.It supervises the whole installation as a central computer
KNX Bus Devices· Bus device components & function· Medium
▸
Correct answer
A — It regulates the interaction between sensors and actuators and has no physical inputs or outputs
Learning tip
Correct: The text defines a controller exactly this way.
View the full question page →
Q138
In start/stop dimming, what does the push button transmit when the rocker is pressed for less than the parameterized time (e.g. < 500 ms)?
- A.A 'start dimming' telegram.
- B.A 'stop dimming' telegram.
- C.A cyclical 'increase brightness by 12.5 %' telegram.
- D.A switching (on/off) telegram.
KNX Bus Devices· Classical application functions: dimming· Medium
▸
Correct answer
D — A switching (on/off) telegram.
Learning tip
Correct: a press below the parameterized threshold is interpreted as a switch command; only a longer press starts dimming.
View the full question page →
Q139
In start/stop dimming, when is the 'stop dimming' telegram sent?
- A.Cyclically, every 12.5 % step.
- B.As soon as the rocker is released.
- C.Automatically once the actuator reaches 100 %.
- D.After a fixed time set in the actuator.
KNX Bus Devices· Classical application functions: dimming· Medium
▸
Correct answer
B — As soon as the rocker is released.
Learning tip
Correct: releasing the rocker generates the single 'stop dimming' telegram.
View the full question page →
Q140
Which device determines the dimming speed in a KNX dimming application?
- A.The push button sensor that starts dimming.
- B.The dimming actuator, via its parameterized dimming speed.
- C.The bus power supply.
- D.The group address used for the telegram.
KNX Bus Devices· Classical application functions: dimming· Medium
▸
Correct answer
B — The dimming actuator, via its parameterized dimming speed.
Learning tip
Correct: every dimming actuator has a parameterized dimming speed; it is an exclusive matter of the actuator.
View the full question page →
Q141
What is T1 in drive control, and when is it typically used?
- A.It is the slats/blinds boundary time, always 500 ms.
- B.It is the blind travel time from top to bottom.
- C.It is the debouncing time for push button interfaces and binary inputs; push buttons normally need none.
- D.It is the actuator's dimming speed.
KNX Bus Devices· Drive control (shutter/blinds)· Medium
▸
Correct answer
C — It is the debouncing time for push button interfaces and binary inputs; push buttons normally need none.
Learning tip
Correct: T1 debounces contact inputs; genuine push buttons normally require no debouncing time.
View the full question page →
Q142
Which rocker action corresponds to which drive-control command?
- A.Brief operation drives blinds up/down; long operation steps the slats.
- B.Brief operation steps the slats; long operation drives the blinds up/down.
- C.Both brief and long operation drive the blinds up/down.
- D.Both brief and long operation only step the slats.
KNX Bus Devices· Drive control (shutter/blinds)· Medium
▸
Correct answer
B — Brief operation steps the slats; long operation drives the blinds up/down.
Learning tip
Correct: a brief press steps the slats, a long press drives the blind up/down.
View the full question page →
Q143
What is the 'device descriptor type 0' of a KNX device?
- A.The KNX serial number assigned in the factory
- B.The individual address of the device
- C.The manufacturer code of the application program
- D.Another name for the mask version, identifying the system-software profile
KNX Bus Devices· Data stored in a device & system profiles· Medium
▸
Correct answer
D — Another name for the mask version, identifying the system-software profile
Learning tip
Correct: The system-software profile is identified by a mask version, also called device descriptor type 0.
View the full question page →
Q144
Which of the following is NOT normally stored in the memory of a KNX device?
- A.The ETS project backup file
- B.The system software (system stack / KNX operating system)
- C.The application program, individual and group addresses and parameters
- D.Temporary values of the system (RAM content) and the application
KNX Bus Devices· Data stored in a device & system profiles· Medium
▸
Correct answer
A — The ETS project backup file
Learning tip
Correct: the ETS project file is not stored in the device. The device retains its operating and configuration data; a BCU key can also be stored in a compatible device to control access. That key is not a recoverable backup of the ETS project: preserving the project and its key remains essential.
View the full question page →
Q145
What happens to the temporary RAM values of a KNX device when the bus power fails?
- A.They are always retained because RAM is non-volatile
- B.They are lost, unless previously saved in non-volatile memory
- C.They are automatically uploaded to the ETS project
- D.They overwrite the mask version
KNX Bus Devices· Data stored in a device & system profiles· Medium
▸
Correct answer
B — They are lost, unless previously saved in non-volatile memory
Learning tip
Correct: RAM (temporary) values are lost on a bus power failure unless the device saved them earlier in non-volatile memory.
View the full question page →
Q146
Under what condition can an application program be downloaded into a BCU?
- A.Any application program can be downloaded into any BCU regardless of manufacturer
- B.Only if the two devices share the same individual address
- C.The manufacturer code of the application program and of the BCU must match
- D.Only if the mask version is set to 0000h first
KNX Bus Devices· Data stored in a device & system profiles· Medium
▸
Correct answer
C — The manufacturer code of the application program and of the BCU must match
Learning tip
Correct: The manufacturer code of the program and of the BCU must match to allow the download.
View the full question page →
Q147
How does an E-mode device report which functionality (channels) it supports?
- A.By means of device descriptor 2
- B.By means of device descriptor type 0 (the mask version)
- C.By downloading product data from the KNX Online Catalog
- D.By its KNX serial number
KNX Bus Devices· Data stored in a device & system profiles· Medium
▸
Correct answer
A — By means of device descriptor 2
Learning tip
Correct: E-mode devices report their supported functionality via device descriptor 2, a different descriptor than S-mode devices.
View the full question page →
Q148
How are E-mode KNX devices linked and their parameters set?
- A.Only by a full ETS download of the application program
- B.Via appropriate hardware settings or via a central controller
- C.By editing the 2-byte mask version in the device
- D.Automatically, with no configuration of any kind
KNX Bus Devices· Data stored in a device & system profiles· Medium
▸
Correct answer
B — Via appropriate hardware settings or via a central controller
Learning tip
Correct: For E-mode devices the linking and parameter setting is ensured via hardware settings or a central controller.
View the full question page →
Q149
When was System 1 technology introduced, and what is its status today?
- A.In 1991, but it has since been removed from the KNX Standard
- B.In the late 1990s, together with System 2 and System 7
- C.With the first generation of KNX devices in 1991; it is still part of the KNX Standard
- D.With ETS6.1.1, as the newest profile
KNX Bus Devices· Data stored in a device & system profiles· Medium
▸
Correct answer
C — With the first generation of KNX devices in 1991; it is still part of the KNX Standard
Learning tip
Correct: System 1 came with the first KNX device generation in 1991 and remains part of the KNX Standard.
View the full question page →
Q150
How many group objects can a System 2/7 device support at most?
- A.254
- B.255
- C.12
- D.65536
KNX Bus Devices· Data stored in a device & system profiles· Medium
▸
Correct answer
A — 254
Learning tip
Correct: System 2/7 devices support up to 254 group objects.
View the full question page →
Q151
When a tool wants to read or write the memory of a System 2, 7 or B device, how must it authorize itself?
- A.With an authorization key of 2 bytes
- B.With an authorization key of 4 bytes
- C.With an authorization key of 6 bytes
- D.No authorization is needed for System 2, 7 or B devices
KNX Bus Devices· Data stored in a device & system profiles· Medium
▸
Correct answer
B — With an authorization key of 4 bytes
Learning tip
Correct: Access requires the tool to first authorize itself with a 4-byte authorization key.
View the full question page →
Q152
From which ETS release is addressing via the KNX serial number supported by default, and what is the alternative before that?
- A.Supported by default from ETS6.1.1; ETS Apps in the MyKNX shop also provide it
- B.Supported by default from ETS4; no apps exist for it
- C.Supported by default from ETS6.1.1; but no other tool can do it
- D.Never supported by ETS; only special hardware can do it
KNX Bus Devices· Data stored in a device & system profiles· Medium
▸
Correct answer
A — Supported by default from ETS6.1.1; ETS Apps in the MyKNX shop also provide it
Learning tip
Correct: The feature is supported by default with ETS6.1.1, and MyKNX-shop ETS Apps also allow reading/writing the individual address without the programming button.
View the full question page →
Q153
What can an ETS end user (system integrator) do with interface objects via the ETS 'Device Editor' App?
- A.Both read and freely rewrite them at will
- B.Only read them; manipulating them requires the deeper knowledge taught in the KNX tutor course
- C.Neither read nor write them
- D.Delete them to reset the device
KNX Bus Devices· Data stored in a device & system profiles· Medium
▸
Correct answer
B — Only read them; manipulating them requires the deeper knowledge taught in the KNX tutor course
Learning tip
Correct: The system integrator cannot manipulate interface objects but can read them with the Device Editor App; manipulation needs tutor-course knowledge.
View the full question page →
Q154
Why are the maxima of 65536 group objects and 65535 group addresses described as essentially theoretical?
- A.Because no KNX device can physically store more than 254 objects
- B.Because the ETS caps every project at 254 group objects
- C.Because they are normally not reached by current applications
- D.Because the values apply only to System 1 devices
KNX Bus Devices· Data stored in a device & system profiles· Medium
▸
Correct answer
C — Because they are normally not reached by current applications
Learning tip
Correct: The text calls them a pure theoretical value, normally not reached by current applications, comparable to the total address capacity of a KNX system.
View the full question page →
Q155
Up to what voltage do the mains-power-system regulations apply that must be observed for a KNX RF installation?
- A.400 V.
- B.1000 V.
- C.690 V.
- D.1500 V.
KNX RF (Radio)· RF commissioning & checks· Medium
▸
Correct answer
B — 1000 V.
Learning tip
Correct: the regulations for mains power systems up to 1000 V are to be observed.
View the full question page →
Q156
How are KNX RF E-Mode devices usually commissioned?
- A.Only with ETS and a full project database.
- B.By assigning individual addresses over an IP backbone.
- C.Via DIP-switches or push-button actions after mounting (ETS optional).
- D.Automatically, with no user action of any kind.
KNX RF (Radio)· RF commissioning & checks· Medium
▸
Correct answer
C — Via DIP-switches or push-button actions after mounting (ETS optional).
Learning tip
Correct: E-Mode teaching-in is usually done with DIP-switches or push-buttons, or by ETS.
View the full question page →
Q157
In the E-Mode Push Button example, how is the desired function confirmed on the receiver?
- A.By briefly tapping the fct button once.
- B.By holding the cfg button for 10 seconds.
- C.By pressing the fct and cfg buttons simultaneously.
- D.By holding the fct button pressed for longer than 2 seconds.
KNX RF (Radio)· RF commissioning & checks· Medium
▸
Correct answer
D — By holding the fct button pressed for longer than 2 seconds.
Learning tip
Correct: the function is confirmed by holding the fct button longer than 2 seconds.
View the full question page →
Q158
How does commissioning KNX RF S-Mode devices compare with commissioning KNX TP S-Mode devices?
- A.It requires no ETS at all, only push-buttons.
- B.It is to a large extent similar to commissioning KNX TP S-Mode devices.
- C.It is completely different and shares no procedures with TP.
- D.It can only be performed over an IP connection.
KNX RF (Radio)· RF commissioning & checks· Medium
▸
Correct answer
B — It is to a large extent similar to commissioning KNX TP S-Mode devices.
Learning tip
Correct: the RF S-Mode procedure is largely similar to the TP S-Mode procedure.
View the full question page →
Q159
Why does each KNX RF line or segment receive its own unique domain address?
- A.To increase the physical radio range of the line.
- B.To set the 868 MHz carrier frequency for that line.
- C.To avoid logical interference between adjacent KNX RF lines.
- D.To supply bus power to the RF devices.
KNX RF (Radio)· RF commissioning & checks· Medium
▸
Correct answer
C — To avoid logical interference between adjacent KNX RF lines.
Learning tip
Correct: the domain address gives each RF line a unique identity to prevent logical interference.
View the full question page →
Q160
What is the maximum number of receivers that may be linked to the same KNX RF sender?
- A.64 (a 65th receiver is prohibited).
- B.128.
- C.32.
- D.Unlimited.
KNX RF (Radio)· RF commissioning & checks· Medium
▸
Correct answer
A — 64 (a 65th receiver is prohibited).
Learning tip
Correct: since the 65th receiver is prohibited, the maximum is 64.
View the full question page →
Q161
What does the functional test of a KNX RF installation involve?
- A.Measuring only the bus voltage at a single point.
- B.Checking the 868 MHz frequency with a spectrum analyser.
- C.Testing only one in ten devices as a representative sample.
- D.Triggering the sensors and observing that the corresponding actuators react, for every taught-in connection.
KNX RF (Radio)· RF commissioning & checks· Medium
▸
Correct answer
D — Triggering the sensors and observing that the corresponding actuators react, for every taught-in connection.
Learning tip
Correct: sensors are triggered/pressed and the actuator reactions observed for all connections.
View the full question page →
Q162
Why must the correct functioning of a KNX RF installation be recorded in a test/acceptance report?
- A.For warranty reasons, to document that the installation functions correctly.
- B.Because ETS refuses to download the project without it.
- C.Only if the customer explicitly requests it.
- D.It is optional and mainly for aesthetics.
KNX RF (Radio)· RF commissioning & checks· Medium
▸
Correct answer
A — For warranty reasons, to document that the installation functions correctly.
Learning tip
Correct: the report documents correct functioning and is kept for warranty reasons.
View the full question page →
Q163
Why is it recommended to record the E-Mode configuration in a list?
- A.Because ETS deletes the project immediately after download.
- B.Because E-Mode sensor-actuator links can be changed very easily, so the installation may no longer match the ordered version.
- C.Because E-Mode devices lose their configuration at every power failure.
- D.Because the domain address changes automatically each day.
KNX RF (Radio)· RF commissioning & checks· Medium
▸
Correct answer
B — Because E-Mode sensor-actuator links can be changed very easily, so the installation may no longer match the ordered version.
Learning tip
Correct: easy changeability means the as-built state can drift, so it should be recorded.
View the full question page →
Q164
How does the free-field range of KNX RF compare with the distance achievable inside a building?
- A.The free-field range is significantly lower than the in-building distance
- B.They are always exactly equal
- C.The free-field range is significantly higher than the in-building distance
- D.The in-building distance is unlimited
KNX RF (Radio)· RF transmission medium· Medium
▸
Correct answer
C — The free-field range is significantly higher than the in-building distance
Learning tip
Correct: free field is the open-space best case and is significantly higher than what is achievable inside a building.
View the full question page →
Q165
Why is the KNX RF free-field range limited to approximately 100 m?
- A.Because of the maximum allowed transmission power and the limited energy available in battery-operated or battery-free devices
- B.Because the 868 MHz band physically cannot travel further
- C.Because ETS caps the transmission distance at 100 m
- D.Because encryption of telegrams shortens the range
KNX RF (Radio)· RF transmission medium· Medium
▸
Correct answer
A — Because of the maximum allowed transmission power and the limited energy available in battery-operated or battery-free devices
Learning tip
Correct: the source names transmission-power limits and the limited energy of battery/battery-free devices.
View the full question page →
Q166
How do walls, ceilings and furniture affect KNX RF signals?
- A.They pass through without any hindrance
- B.They are amplified as they pass through
- C.They are attenuated during penetration and partially reflected
- D.They are converted into a wired telegram
KNX RF (Radio)· RF transmission medium· Medium
▸
Correct answer
C — They are attenuated during penetration and partially reflected
Learning tip
Correct: the source states signals are attenuated on penetration and partly reflected.
View the full question page →
Q167
What happens to KNX RF signals around metallic objects?
- A.Metal has no effect on 868 MHz signals
- B.Metal always amplifies the signal
- C.Metal converts the signal to a lower frequency
- D.They are shielded or reflected, creating a radio shadow on the reverse side where direct reception is not possible
KNX RF (Radio)· RF transmission medium· Medium
▸
Correct answer
D — They are shielded or reflected, creating a radio shadow on the reverse side where direct reception is not possible
Learning tip
Correct: metallic objects shield/reflect signals and produce radio shadows behind them.
View the full question page →
Q168
Which statement about reflections of KNX RF signals is correct?
- A.Reflections can have both a positive and a negative effect
- B.Reflections are always beneficial
- C.Reflections are always harmful
- D.Reflections never occur in the 868 MHz band
KNX RF (Radio)· RF transmission medium· Medium
▸
Correct answer
A — Reflections can have both a positive and a negative effect
Learning tip
Correct: the source says reflections may be positive or negative depending on the situation.
View the full question page →
Q169
When should structural interfering factors for KNX RF be taken into account?
- A.Only after commissioning, if problems appear
- B.They never need to be considered
- C.Already during the building planning stage, when carefully selecting the device mounting sites
- D.Only automatically by the ETS during programming
KNX RF (Radio)· RF transmission medium· Medium
▸
Correct answer
C — Already during the building planning stage, when carefully selecting the device mounting sites
Learning tip
Correct: the source says interfering factors must be considered at the planning stage and mounting sites chosen carefully.
View the full question page →
Q170
If RF device mounting sites cannot be freely selected, how is a good radio connection usually achieved?
- A.By increasing the mains voltage at the device
- B.By switching the devices to the 2.4 GHz band
- C.By removing every possible reflection from the room
- D.By using a KNX RF repeater
KNX RF (Radio)· RF transmission medium· Medium
▸
Correct answer
D — By using a KNX RF repeater
Learning tip
Correct: the source recommends a KNX RF repeater when mounting sites are constrained.
View the full question page →
Q171
What bit rate does the KNX RF description give for the information to be transferred?
- A.16384 bits per second
- B.16384 bits per minute
- C.1638 bits per second
- D.163840 bits per second
KNX RF (Radio)· KNX Ready, RF-Multi, bus access & telegram structure· Medium
▸
Correct answer
A — 16384 bits per second
Learning tip
Correct: the source states a bit rate of 16384 bits per second, modulated with Manchester coding.
View the full question page →
Q172
What is the stated advantage of the Manchester coding used in KNX RF?
- A.A larger available frequency band
- B.Increased transmission reliability, with an edge transition in the centre of each bit
- C.Higher maximum transmission power
- D.Elimination of the need for a preamble
KNX RF (Radio)· KNX Ready, RF-Multi, bus access & telegram structure· Medium
▸
Correct answer
B — Increased transmission reliability, with an edge transition in the centre of each bit
Learning tip
Correct: the source names increased transmission reliability, thanks to the mid-bit 0/1 transition that keeps clocks synchronised.
View the full question page →
Q173
The KNX RF duty cycle limits how long a device may transmit. What is that limit?
- A.10 %, i.e. a maximum of about 6 minutes per hour
- B.1 %, i.e. a maximum of 3.6 seconds per hour
- C.100 %, with no time limit
- D.1 %, i.e. a maximum of 36 seconds of transmission per hour
KNX RF (Radio)· KNX Ready, RF-Multi, bus access & telegram structure· Medium
▸
Correct answer
D — 1 %, i.e. a maximum of 36 seconds of transmission per hour
Learning tip
Correct: the duty cycle is 1 %, equal to a maximum transmission duration of 36 seconds per hour.
View the full question page →
Q174
How does the data rate of KNX RF-Multi slow channels compare with the fast channels?
- A.It is one quarter of the fast-channel data rate
- B.It is the same as the fast channels
- C.It is half the data rate of the fast channels, mainly because of the extended preamble
- D.It is double the data rate of the fast channels
KNX RF (Radio)· KNX Ready, RF-Multi, bus access & telegram structure· Medium
▸
Correct answer
C — It is half the data rate of the fast channels, mainly because of the extended preamble
Learning tip
Correct: slow channels run at half the speed of fast channels, mainly due to the longer preamble.
View the full question page →
Q175
By how much can sleep mode reduce a KNX RF-Multi device's energy consumption?
- A.Up to 99 % for both fast and slow channels
- B.Up to 99 % for fast channels and up to 80 % for slow channels
- C.Up to 80 % for fast channels and up to 99 % for slow channels
- D.Up to 50 % for fast channels and up to 70 % for slow channels
KNX RF (Radio)· KNX Ready, RF-Multi, bus access & telegram structure· Medium
▸
Correct answer
C — Up to 80 % for fast channels and up to 99 % for slow channels
Learning tip
Correct: sleep mode saves up to 80 % on fast channels and up to 99 % on slow channels, the device being woken periodically to receive.
View the full question page →
Q176
What preamble length does a KNX RF-Multi sender use in a slow channel (compared with 15 ms fast and 5 ms Ready)?
- A.50 ms
- B.5 ms
- C.15 ms
- D.500 ms
KNX RF (Radio)· KNX Ready, RF-Multi, bus access & telegram structure· Medium
▸
Correct answer
D — 500 ms
Learning tip
Correct: a slow-channel RF-Multi sender uses a 500 ms preamble, letting receivers sleep longer and save battery.
View the full question page →
Q177
Why does KNX RF natively support long frames?
- A.To remove the need for a domain address or serial number
- B.To support the KNX Secure Application Layer (authentication and encryption), so the media coupler is not the security weak point
- C.To let unidirectional devices receive telegrams
- D.To raise the maximum transmission power above 25 mW
KNX RF (Radio)· KNX Ready, RF-Multi, bus access & telegram structure· Medium
▸
Correct answer
B — To support the KNX Secure Application Layer (authentication and encryption), so the media coupler is not the security weak point
Learning tip
Correct: long frames carry the KNX Secure Application Layer, giving authentication and encryption and removing the media coupler as the weak point.
View the full question page →
Q178
How does a unidirectional KNX RF device handle bus access and collisions?
- A.It waits for the channel to be free, then transmits
- B.It never resends, so a collided telegram is simply lost
- C.It sends immediately; on a collision it resends, but the 1 % duty cycle makes collisions nearly excluded
- D.It requests a time slot from a central controller first
KNX RF (Radio)· KNX Ready, RF-Multi, bus access & telegram structure· Medium
▸
Correct answer
C — It sends immediately; on a collision it resends, but the 1 % duty cycle makes collisions nearly excluded
Learning tip
Correct: unidirectional devices transmit at once and resend if a collision happens, which is rare thanks to the 1 % duty cycle.
View the full question page →
Q179
How does a bidirectional KNX RF device access the bus?
- A.It transmits immediately regardless of channel state
- B.It transmits continuously until an acknowledgement arrives
- C.It can only receive and never transmits
- D.It checks whether the channel is free; if it is occupied it waits until free, then transmits
KNX RF (Radio)· KNX Ready, RF-Multi, bus access & telegram structure· Medium
▸
Correct answer
D — It checks whether the channel is free; if it is occupied it waits until free, then transmits
Learning tip
Correct: bidirectional devices listen first and only send once the channel is free.
View the full question page →
Q180
Which statement best describes the structure of a KNX RF telegram?
- A.It consists of several data blocks separated by checksum bytes; the blocks at the start and end synchronise the receivers to the transmitter
- B.It is a single continuous block with no internal checksums
- C.It contains only useful data and no addressing information
- D.Its start and end blocks carry the switching command
KNX RF (Radio)· KNX Ready, RF-Multi, bus access & telegram structure· Medium
▸
Correct answer
A — It consists of several data blocks separated by checksum bytes; the blocks at the start and end synchronise the receivers to the transmitter
Learning tip
Correct: a KNX RF telegram is several data blocks separated by checksums, with start/end blocks used for synchronisation.
View the full question page →
Q181
Which information does the control field of the first data block carry?
- A.Only the CRC used for error detection
- B.The switching or dimming command to be executed
- C.Telegram length, device type (uni-/bidirectional), transmission quality (signal strength) and battery status
- D.The group address assigned by ETS
KNX RF (Radio)· KNX Ready, RF-Multi, bus access & telegram structure· Medium
▸
Correct answer
C — Telegram length, device type (uni-/bidirectional), transmission quality (signal strength) and battery status
Learning tip
Correct: the control field holds the telegram length, the device type, the transmission quality and the battery status of battery-operated devices.
View the full question page →
Q182
In the first data block, which identifier is sent after the control field for an RF S-Mode device?
- A.The group address
- B.The KNX serial number
- C.The individual (physical) address
- D.The domain address
KNX RF (Radio)· KNX Ready, RF-Multi, bus access & telegram structure· Medium
▸
Correct answer
D — The domain address
Learning tip
Correct: for RF S-Mode devices a domain address is sent after the control field (E-Mode devices send the serial number).
View the full question page →
Q183
For KNX RF devices in E mode, which statement about the KNX serial number is correct?
- A.It is a unique identifier programmed during manufacturing, is not modifiable, and is stored in the receiver as the source address
- B.It is assigned by the installer with ETS during commissioning
- C.It changes each time the device transmits
- D.It is only used inside one installation and cannot distinguish neighbouring installations
KNX RF (Radio)· KNX Ready, RF-Multi, bus access & telegram structure· Medium
▸
Correct answer
A — It is a unique identifier programmed during manufacturing, is not modifiable, and is stored in the receiver as the source address
Learning tip
In E mode, the unique factory-programmed KNX serial number is transmitted and stored in the receiver as the source address. In S mode, distinguish the transmitted domain address from this serial number.
View the full question page →
Q184
Which devices are typically unidirectional 'send-only' KNX RF devices?
- A.Mains-powered relay actuators controlling lighting
- B.Media couplers linking RF to TP
- C.Battery-operated sensors and detectors such as push-button transmitters, binary inputs and door/window contacts
- D.KNX RF repeaters
KNX RF (Radio)· KNX Ready, RF-Multi, bus access & telegram structure· Medium
▸
Correct answer
C — Battery-operated sensors and detectors such as push-button transmitters, binary inputs and door/window contacts
Learning tip
Correct: send-only unidirectional devices are mainly battery-operated sensors/detectors like hand-held or wall transmitters, binary inputs and door/window contacts.
View the full question page →
Q185
Which statement best describes the topology of devices in a KNX RF installation?
- A.They must be grouped into areas and lines joined by couplers, exactly like KNX TP.
- B.They are arranged in a star around a central RF controller that routes every telegram.
- C.They follow no fixed hierarchical arrangement; within radio range any sensor can communicate with any actuator.
- D.Each device may communicate with only one paired device, never with several actuators.
KNX RF (Radio)· RF topology & combination of media· Medium
▸
Correct answer
C — They follow no fixed hierarchical arrangement; within radio range any sensor can communicate with any actuator.
Learning tip
Correct: the source says RF devices are not subject to a hierarchical arrangement and each sensor within range can reach each actuator.
View the full question page →
Q186
In a KNX RF telegram, what does an E-Mode device use as its device identifier?
- A.Its domain address.
- B.Its individual (physical) address such as 1.1.5.
- C.The group address of the linked actuator.
- D.Its serial number.
KNX RF (Radio)· RF topology & combination of media· Medium
▸
Correct answer
D — Its serial number.
Learning tip
Correct: each KNX RF E-Mode device sends its serial number as device identifier.
View the full question page →
Q187
What does a KNX RF S-Mode device send as its device identifier?
- A.Its domain address.
- B.Its serial number.
- C.A hardware MAC address.
- D.Its area/line topology address.
KNX RF (Radio)· RF topology & combination of media· Medium
▸
Correct answer
A — Its domain address.
Learning tip
Correct: KNX RF S-Mode devices send their domain address as device identifier.
View the full question page →
Q188
With how many KNX RF repeaters can the radio range of an installation be extended?
- A.Up to 1.
- B.Up to 2.
- C.Up to 4.
- D.An unlimited number.
KNX RF (Radio)· RF topology & combination of media· Medium
▸
Correct answer
B — Up to 2.
Learning tip
Correct: the range can be extended with up to two KNX RF repeaters, across several floors.
View the full question page →
Q189
For KNX RF S-Mode devices, how is it defined which telegrams a media coupler transfers?
- A.Only via ETS, comparable to the function of a line coupler (bus line to RF line).
- B.Only by teaching-in with the coupler's push-buttons, without ETS.
- C.Automatically, based on measured signal strength.
- D.It is fixed by the manufacturer and cannot be configured.
KNX RF (Radio)· RF topology & combination of media· Medium
▸
Correct answer
A — Only via ETS, comparable to the function of a line coupler (bus line to RF line).
Learning tip
Correct: for S-Mode this is done only via ETS, like a line coupler.
View the full question page →
Q190
When the Download button in the main toolbar is clicked, how does ETS decide what to download?
- A.It always downloads the full application and address
- B.It selects the best download option for the device based on the device's flags
- C.It selects based on the device's bus current
- D.It asks the user to choose every time via a wizard
ETS6 Professional· Bars, views, columns, search & filter· Medium
▸
Correct answer
B — It selects the best download option for the device based on the device's flags
Learning tip
Correct: When the Download button is clicked, ETS selects the best download option for this device based on the device's flags.
View the full question page →
Q191
Which numeric keys collapse and expand tree branches in the Tree view?
- A.'+' expands and '-' collapses
- B.F2 expands and ENTER collapses
- C.'/' collapses and '*' expands
- D.'*' collapses and '/' expands
ETS6 Professional· Bars, views, columns, search & filter· Medium
▸
Correct answer
C — '/' collapses and '*' expands
Learning tip
Correct: The numeric key '/' collapses a branch and '*' expands it.
View the full question page →
Q192
How many search items will be saved?
- A.Up to 15
- B.Up to 5
- C.Up to 10
- D.Up to 20
ETS6 Professional· Bars, views, columns, search & filter· Medium
▸
Correct answer
A — Up to 15
Learning tip
Correct: Up to 15 search items will be saved, sorted chronologically with the most recent on top.
View the full question page →
Q193
Which download flags are involved in the 'Download All' option?
- A.Par and Grp only
- B.Adr, Prg, Par and Grp
- C.Adr only
- D.Prg only
ETS6 Professional· Commissioning, download, unload & restart· Medium
▸
Correct answer
B — Adr, Prg, Par and Grp
Learning tip
Correct: Download All transfers all project data and involves the Adr, Prg, Par and Grp flags.
View the full question page →
Q194
What does the 'Download Partial' option transfer to the device(s)?
- A.All project data, exactly like Download All
- B.Only the individual address
- C.Only the parts changed in ETS and not downloaded before (Parameters/Addresses and Application programs)
- D.Nothing until the device is restarted
ETS6 Professional· Commissioning, download, unload & restart· Medium
▸
Correct answer
C — Only the parts changed in ETS and not downloaded before (Parameters/Addresses and Application programs)
Learning tip
Correct: Download Partial sends only the changed, not-yet-downloaded parts, split into Parameters/Addresses and Application programs.
View the full question page →
Q195
Under what condition can ETS assign an individual address without you physically pressing the device's download button?
- A.When the device supports the KNX Serial Number feature and its serial number is entered in ETS
- B.Whenever the device is powered on the bus
- C.Only after the application program has been downloaded
- D.Never; the download button must always be pressed
ETS6 Professional· Commissioning, download, unload & restart· Medium
▸
Correct answer
A — When the device supports the KNX Serial Number feature and its serial number is entered in ETS
Learning tip
Correct: With the KNX Serial Number entered, ETS can address the device without a button press.
View the full question page →
Q196
Which Unload variant requires the device to be in Programming Mode?
- A.Unload Application (only)
- B.Both variants require Programming Mode
- C.Unload Application and Address
- D.Neither variant requires Programming Mode
ETS6 Professional· Commissioning, download, unload & restart· Medium
▸
Correct answer
C — Unload Application and Address
Learning tip
Correct: Unload Application and Address requires the device to be in Programming Mode.
View the full question page →
Q197
For a KNX RF S-Mode device whose programming mode is not switched off manually, what happens?
- A.The device automatically switches off programming mode after 40 minutes
- B.Programming mode stays on until the next download
- C.The device automatically switches off programming mode after 4 minutes
- D.The device is damaged after 4 minutes in programming mode
ETS6 Professional· Diagnostics, monitors & project check· Medium
▸
Correct answer
C — The device automatically switches off programming mode after 4 minutes
Learning tip
Correct: The source states RF S-Mode devices auto switch off programming mode after 4 minutes.
View the full question page →
Q198
While the Bus Monitor is recording, which statement is true about other bus diagnostics?
- A.All other diagnostics remain fully available
- B.You cannot check an individual address, do a line scan or search for programming-mode devices, because the Bus Monitor needs exclusive bus access
- C.Only downloads are blocked, everything else works
- D.Another Bus Monitor can run in parallel on the same interface
ETS6 Professional· Diagnostics, monitors & project check· Medium
▸
Correct answer
B — You cannot check an individual address, do a line scan or search for programming-mode devices, because the Bus Monitor needs exclusive bus access
Learning tip
Correct: The Bus Monitor requires exclusive bus access, so those functions are unavailable during its recording.
View the full question page →
Q199
Which monitor lets you continue to check individual addresses, do a line scan or search for programming-mode devices while it is recording?
- A.The Bus Monitor, because it records everything
- B.Neither monitor allows any other diagnostics during recording
- C.The Group Monitor, because it does not require exclusive bus access
- D.Both monitors always allow all other diagnostics
ETS6 Professional· Diagnostics, monitors & project check· Medium
▸
Correct answer
C — The Group Monitor, because it does not require exclusive bus access
Learning tip
Correct: The Group Monitor shares the bus, so those functions remain available during its session.
View the full question page →
Q200
How many levels/checks does the Project Check perform, and which are they?
- A.Three: Device, Group address and Topology checks only
- B.Four: Device, Group address, Topology and Bus Traffic checks
- C.Five: Device, Group address, Topology, Security and Licensing checks
- D.Five: Device check, Group address check, Topology check, Product Information check, and Checks for projects imported from earlier ETS versions
ETS6 Professional· Diagnostics, monitors & project check· Medium
▸
Correct answer
D — Five: Device check, Group address check, Topology check, Product Information check, and Checks for projects imported from earlier ETS versions
Learning tip
Correct: The source lists these five levels of the Project Check.
View the full question page →
Q201
In the Topology Check, which default averages are used when the current properties are not available?
- A.320 mA per device, 10 mA per power supply
- B.20 mA per device, 640 mA per power supply
- C.10 mA assumed per device, 320 mA assumed per power supply
- D.10 mA per device, 160 mA per power supply
ETS6 Professional· Diagnostics, monitors & project check· Medium
▸
Correct answer
C — 10 mA assumed per device, 320 mA assumed per power supply
Learning tip
Correct: The source specifies 10 mA per device and 320 mA per power supply as the assumed averages.
View the full question page →
Q202
At what level does the Online Error Diagnostics wizard check for installation errors, and what does it require?
- A.At the functionality level, i.e. group address level, and it requires an online connection to the bus
- B.At the topology level, and it works offline
- C.At the individual-address level only, with no bus needed
- D.At the licensing level, requiring a dongle
ETS6 Professional· Diagnostics, monitors & project check· Medium
▸
Correct answer
A — At the functionality level, i.e. group address level, and it requires an online connection to the bus
Learning tip
Correct: The source states it checks at group-address (functionality) level and needs an online bus connection.
View the full question page →
Q203
What can the dashboard's search bar do?
- A.Search only projects in the local list
- B.Search only archived projects
- C.Quickly search for projects regardless of location - the local list or anywhere in the archive
- D.Search the online product catalog only
ETS6 Professional· Dashboard, local projects & restore points· Medium
▸
Correct answer
C — Quickly search for projects regardless of location - the local list or anywhere in the archive
Learning tip
Correct: the search bar spans the local list and the archive.
View the full question page →
Q204
Which buttons does the dashboard's main toolbar contain?
- A.Settings, Help and New Project
- B.New Project and Import Project
- C.Start Project Wizard and Export
- D.Settings and Help
ETS6 Professional· Dashboard, local projects & restore points· Medium
▸
Correct answer
D — Settings and Help
Learning tip
Correct: the main toolbar contains the Settings and Help buttons.
View the full question page →
Q205
What is the purpose of project restore points?
- A.To open an ETS project in one of its earlier stages
- B.To permanently delete old project versions
- C.To export a project to knxproj format
- D.To lock a project against editing
ETS6 Professional· Dashboard, local projects & restore points· Medium
▸
Correct answer
A — To open an ETS project in one of its earlier stages
Learning tip
Correct: restore points open a project in an earlier stage.
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Q206
What is the minimum CPU requirement for installing ETS6?
- A.A processor of at least 1 GHz
- B.A processor of at least 3 GHz
- C.A processor of at least 2.5 GHz
- D.A processor of at least 2 GHz
ETS6 Professional· ETS concept & requirements· Medium
▸
Correct answer
D — A processor of at least 2 GHz
Learning tip
Correct: the minimum CPU is at least 2 GHz.
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Q207
What is the minimum storage (disk space) requirement for ETS6?
- A.At least 10 GB
- B.At least 20 GB
- C.At least 40 GB
- D.At least 2 GB
ETS6 Professional· ETS concept & requirements· Medium
▸
Correct answer
B — At least 20 GB
Learning tip
Correct: the minimum storage is 20 GB.
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Q208
What is the minimum screen resolution required by ETS6?
- A.800 x 600
- B.1280 x 1024
- C.1024 x 768
- D.1920 x 1080
ETS6 Professional· ETS concept & requirements· Medium
▸
Correct answer
C — 1024 x 768
Learning tip
Correct: the minimum screen resolution is 1024 x 768.
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Q209
Which operating systems are exclusively supported for an ETS6 installation?
- A.Windows 10 (Version 20H2 or higher) and Windows 11
- B.Windows 10, Windows 11 and macOS
- C.Any Windows version plus Linux
- D.Windows 7 and Windows 8
ETS6 Professional· ETS concept & requirements· Medium
▸
Correct answer
A — Windows 10 (Version 20H2 or higher) and Windows 11
Learning tip
Correct: these are the only supported operating systems.
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Q210
With an ETS Demo license, what is the maximum number of devices a project may contain in order to be exported?
- A.5 devices
- B.20 devices
- C.10 devices
- D.Unlimited
ETS6 Professional· Import/export, product import & project design· Medium
▸
Correct answer
A — 5 devices
Learning tip
Correct: a Demo license can export projects with a maximum of 5 devices.
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Q211
How many devices can a project contain, at most, to be exported with an ETS Lite license?
- A.5 devices
- B.20 devices
- C.50 devices
- D.Unlimited
ETS6 Professional· Import/export, product import & project design· Medium
▸
Correct answer
B — 20 devices
Learning tip
Correct: a Lite license can export a project with a maximum of 20 devices.
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Q212
What size is the Domain Address that ETS automatically generates for a new RF line?
- A.3 bytes
- B.2 bytes (like a group address)
- C.16 bytes
- D.6 bytes
ETS6 Professional· Import/export, product import & project design· Medium
▸
Correct answer
D — 6 bytes
Learning tip
Correct: ETS creates a unique 6-byte Domain Address for a new RF line.
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Q213
Immediately after running the ETS6 setup on a fresh PC and starting ETS6, in what state does it run?
- A.As demo, because the setup does not add a license
- B.As ETS6 Professional by default
- C.It refuses to start until a dongle is plugged in
- D.As ETS6 Lite, the free edition
ETS6 Professional· ETS settings, licensing & troubleshooting· Medium
▸
Correct answer
A — As demo, because the setup does not add a license
Learning tip
Correct: There is only one ETS6 setup and it installs ETS6 as demo; the setup does not add a license.
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Q214
After adding a license to the ETS6 software package, ETS6 becomes one of which editions?
- A.ETS6 Professional, ETS6 Lite or ETS6 Demo
- B.ETS6 Professional, ETS6 Home or ETS6 Lite
- C.ETS6 Professional or ETS6 Bundle only
- D.ETS6 Standard, Home or Lite
ETS6 Professional· ETS settings, licensing & troubleshooting· Medium
▸
Correct answer
B — ETS6 Professional, ETS6 Home or ETS6 Lite
Learning tip
Correct: Once a license is added, ETS6 becomes ETS6 Professional, ETS6 Home or ETS6 Lite.
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Q215
Which statement correctly distinguishes the two ways to license ETS6 and its Apps?
- A.Guided licensing never needs internet; manual licensing always needs internet
- B.Both methods require a permanent internet connection
- C.Neither method uses the internet at all
- D.Guided licensing needs internet only at the time of licensing; manual licensing needs no internet at the time of licensing
ETS6 Professional· ETS settings, licensing & troubleshooting· Medium
▸
Correct answer
D — Guided licensing needs internet only at the time of licensing; manual licensing needs no internet at the time of licensing
Learning tip
Correct: Guided licensing requires an active internet connection only at the time of licensing, while manual licensing does not require internet at the time of licensing.
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Q216
Which logging levels does ETS define, and which is the default?
- A.Standard and Extended, with Standard as the default
- B.Standard and Extended, with Extended as the default
- C.Basic and Full, with Full as the default
- D.Minimal, Standard and Extended, with Standard as the default
ETS6 Professional· ETS settings, licensing & troubleshooting· Medium
▸
Correct answer
A — Standard and Extended, with Standard as the default
Learning tip
Correct: Two logging levels are defined, Standard and Extended; by default the logging level is set to Standard.
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Q217
For the Standard log level, how many events (n) before the trigger event are recorded to the log file?
- A.1000
- B.500
- C.250
- D.5000
ETS6 Professional· ETS settings, licensing & troubleshooting· Medium
▸
Correct answer
B — 500
Learning tip
Correct: For the Standard log level, n = 500 (trigger event type = ERROR).
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Q218
In ETS6, where is the actual work within a project primarily carried out?
- A.In the panels (Project Design views)
- B.In the Dashboard start screen
- C.In the Settings dialog
- D.In the online KNX Help Center
ETS6 Professional· Project design panels· Medium
▸
Correct answer
A — In the panels (Project Design views)
Learning tip
Correct: The source says the actual work within an ETS project is primarily done in panels.
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Q219
What is the Buildings panel primarily used for?
- A.Generating and defining group addresses
- B.Defining the bus structure and assigning individual addresses
- C.Creating the building structure and placing devices at their physical location
- D.Searching and inserting KNX products
ETS6 Professional· Project design panels· Medium
▸
Correct answer
C — Creating the building structure and placing devices at their physical location
Learning tip
Correct: The Buildings panel creates building structures (Buildings, Functions, Trades) and lets you place devices into building elements.
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Q220
What is the Group Address panel used for?
- A.Creating the physical building structure
- B.Generating and defining group addresses
- C.Defining the bus structure and assigning individual addresses
- D.Producing project documentation and reports
ETS6 Professional· Project design panels· Medium
▸
Correct answer
B — Generating and defining group addresses
Learning tip
Correct: The source says the Group Address panel is used to generate and define group addresses.
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Q221
What is the Topology panel used for?
- A.To define the actual bus structure and assign individual addresses to devices
- B.To generate and define group addresses
- C.To create the physical building structure
- D.To produce the project's parts list
ETS6 Professional· Project design panels· Medium
▸
Correct answer
A — To define the actual bus structure and assign individual addresses to devices
Learning tip
Correct: The source says the Topology panel defines the actual bus structure and the assignment of individual addresses.
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Q222
How are devices shown in the Devices panel?
- A.All devices in one list without any categorization
- B.Grouped by building and room
- C.Grouped by line and area
- D.Grouped by manufacturer
ETS6 Professional· Project design panels· Medium
▸
Correct answer
A — All devices in one list without any categorization
Learning tip
Correct: The source says all devices are displayed in one list without any categorization.
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Q223
A device has been locked with the project's BCU Key during download, and the key is now lost. Who can reset it?
- A.The KNX Association, via a master key
- B.Any ETS6 Professional user with the project open
- C.Only the manufacturer
- D.The device resets itself automatically after 24 hours
ETS6 Professional· Project creation, wizard & details· Medium
▸
Correct answer
C — Only the manufacturer
Learning tip
Correct: only the manufacturer is able to reset the BCU key of a password-protected device once the key is lost or forgotten.
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Q224
Under what condition can a project password be disabled (cleared)?
- A.At any time, by clicking 'Clear Password'
- B.Only after the project has been exported
- C.Only by the KNX Association
- D.Only if there are no devices in secure mode and no device certificates
ETS6 Professional· Project creation, wizard & details· Medium
▸
Correct answer
D — Only if there are no devices in secure mode and no device certificates
Learning tip
Correct: disabling a project password is only possible when there are no devices in secure mode or device certificates.
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Q225
What does assigning a project password do?
- A.Locks the project (no open/edit without it) and encrypts the exported project so its data cannot be read
- B.Only greys out the Details tab, with no effect on export
- C.Encrypts the export but still lets anyone open the project locally
- D.Prevents the project from ever being deleted
ETS6 Professional· Project creation, wizard & details· Medium
▸
Correct answer
A — Locks the project (no open/edit without it) and encrypts the exported project so its data cannot be read
Learning tip
Correct: the password locks the project and encrypts it during export, so the exported data cannot be accessed (e.g. with a ZIP program).
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Q226
What is the maximum length of a project password, and which characters are allowed?
- A.Maximum 8 characters, letters and digits only
- B.Maximum 20 characters, any ASCII characters
- C.Maximum 16 characters, any ASCII characters
- D.Maximum 64 characters, any Unicode characters
ETS6 Professional· Project creation, wizard & details· Medium
▸
Correct answer
B — Maximum 20 characters, any ASCII characters
Learning tip
Correct: a project password can be at most 20 characters long and any ASCII characters can be used (and the entry is case-sensitive).
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