medium KNX Advanced exam questions
KNX Advanced Certification mock exam questions selected at medium level. Ideal for consolidating what you've learned and gauging your real level.
Medium level questions
Q01
DPT 20.102 (HVAC Mode) encodes the four standard modes - Comfort (1), Standby (2), Economy (3) and Building Protection (4) - and is applied as a cascade from the currently active mode.TrueFalse4. HVAC Control· HVAC-Modi· MediumCorrect answerTrueLearning tipThe four modes form a hierarchy ranked by comfort/economy. Comfort uses the full occupant setpoint; Standby applies a small offset (deltaT of 2-4 degrees C) for short absences; Economy applies a larger offset (deltaT of 4-6 degrees C) for long absences and night-time; Building Protection enforces a safety setpoint (frost protection or overheat protection). The DPT 20.102 value is carried as a single byte in the telegram.
Q02
A KNX/DALI gateway allows up to 64 DALI ballasts on a single DALI bus to be driven from KNX commands, with addressing either individual or by DALI group.TrueFalse5. Lighting Control· DALI-Gateway· MediumCorrect answerTrueLearning tipStandard DALI supports a maximum of 64 ballasts per bus. The gateway exposes those ballasts as KNX Group Objects (individual ballast or DALI group). On the KNX side, the typical bindings use DPT 1.001 (on/off), DPT 5.001 (dimming), DPT 232.600 (colour tunable white) and DPT 17/18 (DALI scenes mapped to KNX scene values). Modern gateways also support DALI-2 with automatic device registration.
Q03
Tunable White control (variable colour temperature, e.g. 2700 K warm to 6500 K cool) over KNX typically uses two distinct DPTs: one for the overall intensity (DPT 5.001, %) and one for the colour temperature (DPT 7.600, K).TrueFalse5. Lighting Control· Tunable White· MediumCorrect answerTrueLearning tipDPT 7.600 is Absolute Colour Temperature in Kelvin (16 bits, technical range 0-65535 but usable range 2000-10000 K). Combined with DPT 5.001 for intensity, it allows independent control of the two dimensions. This is the standard binding for Tunable White luminaires using a warm-white plus cool-white dual-channel LED.
Q04
A KNX presence detector configured with a 15-minute timeout keeps the lighting on for that duration after the last detection, then automatically switches it off.TrueFalse5. Lighting Control· Präsenzerkennung· MediumCorrect answerTrueLearning tipOff-delay values typically range from 5 to 30 minutes depending on usage: around 15 minutes for offices, 3 minutes for corridors, 5 minutes for restrooms. The detector sends DPT 1.001 = 1 on detection and DPT 1.001 = 0 once the off-delay elapses. It is commonly combined with a lux sensor so the light is not switched on when daylight is already sufficient.
Source: Theben PIR detector applicationQ05
In KNX, a "Technical Alarm" (water leak, smoke detection, equipment fault) is distinct from an "Intrusion Alarm" (break-in), because the EN 50131 standards require a separate certified system for anti-intrusion alarms.TrueFalse6. Security Technology· Einbruch vs. Technische Meldung· MediumCorrect answerTrueLearning tipThe distinction is both regulatory and functional. A Technical Alarm can be 100% KNX (smoke detector, flood contact, technical fault) and is not certified against burglary. An Intrusion Alarm must be a dedicated EN 50131 certified system (grade 1-4), self-contained with a backup battery and a link to a monitoring centre. KNX can interact WITH the intrusion alarm (receive its states for visualisation, trigger an "away" mode) but cannot replace it.
Q06
A KNX/Sonos (or KNX/multi-room audio) gateway makes it possible to control the volume, the source and play/pause of every audio zone from standard KNX commands (DPT 5.001 for volume, DPT 1.001 for play/pause).TrueFalse10. Multimedia· Audio-Zone· MediumCorrect answerTrueLearning tipGateway architecture from KNX to an audio system (Sonos, Bose, Nuvo, Russound) with the following standard mapping: DPT 5.001 for volume 0-100%; DPT 1.001 for play/pause and mute/unmute; DPT 5.010 for source selection (1-N); DPT 17.001 or DPT 16.001 for playlist selection by name. This enables audio integration in KNX-driven scenarios such as "evening", "wake-up" or "leaving home".
Q07
To transmit cumulative active energy consumption in kWh from a KNX meter, DPT 13.013 (Active Energy in kWh, signed 32-bit) is more appropriate than DPT 14.056 (Power), which encodes an instantaneous power in W.TrueFalse11. Smart Metering· Zähler-DPT· MediumCorrect answerTrueLearning tipThe semantic distinction is critical. DPT 13.013 (kWh, signed 32-bit) represents cumulative energy — a counter that only goes up — with a range of about plus or minus 2.1 billion kWh, more than enough for decades of use. DPT 14.056 (W, 32-bit float) represents instantaneous power that varies in real time with the active loads. The two are complementary on a smart meter: 13.013 for billing, 14.056 for real-time monitoring.
Q08
A standard KNX end-of-works deliverable typically includes the .knxproj project file, printed documentation (topology, Group Address table, electrical schematics), functional-test reports, user training, and a separate .knxkeys keyring file when KNX Secure is used.TrueFalse13. Project best practices· Projektdokumentation· MediumCorrect answerTrueLearning tipA professional integrator's handover package usually contains: (1) the signed/dated/versioned .knxproj file, (2) printed topology (devices, IPs, Individual Addresses, lines/areas), (3) a Group Address list with name, DPT, bindings and description, (4) electrical schematics (bus wiring, power supply, terminations), (5) signed functional-test reports, (6) a 2-4 h end-user training session, (7) the .knxkeys keyring if Secure is used, with the password transmitted by a separate channel, and (8) a maintenance datasheet listing key contacts and SLA terms. This aligns naturally with ISO 9001 and company-level certifications.
Q09
A typical 3-5 year KNX maintenance contract usually includes: an annual preventive visit (PSU check, bus load, vendor firmware updates), curative intervention within 4-24 h depending on SLA, an automatic monthly backup of the ETS project, and an annual parameter review with the client.TrueFalse13. Project best practices· Wartungsverträge· MediumCorrect answerTrueLearning tipA standard B2B KNX maintenance contract covers (1) an annual visit auditing PSUs, bus load (target below 30%), error counters and preventive replacement of critical components; (2) intervention SLAs typically 4 h business hours, 24 h business hours or 48 h depending on tier (tier 1 critical production, tier 3 comfort); (3) an automatic monthly backup of the .knxproj file to encrypted cloud storage; (4) catalogue and application-program updates; and (5) an annual review meeting with the client on observed usage and parameter adjustments. Pricing is usually 5-15% of the initial install cost per year. The recurring revenue is essential to integrator stability.
Q10
In a KNX TP power supply, the choke presents a low impedance to DC and a high impedance to AC.TrueFalse3. Power supplies· Spannungsversorgung· MediumCorrect answerTrueLearning tipThe choke is an inductor (typically several mH) wired in series between the DC source and the bus line. By the nature of an inductor, its impedance is essentially zero for direct current and rises with frequency for alternating signals. The DC bus voltage (around 29 V) therefore passes through unimpeded to power the devices, while the AC components of the bus telegrams (the 9600 bit/s modulated signal, with a bandwidth around 10 kHz) see a high impedance and are not short-circuited by the supply. Without the choke, the supply's low DC source impedance would swallow every telegram.
Q11
DALI devices can be commissioned through the KNX/DALI gateway, typically using ETS apps or manufacturer-specific tools.TrueFalse5. Lighting Control· Beleuchtung & Beschattung· MediumCorrect answerTrueLearning tipModern KNX/DALI gateways embed a DALI master controller that performs short-address assignment, group setup and scene programming on behalf of the installer. Many manufacturers ship a dedicated ETS App that exposes this DALI commissioning inside the ETS user interface, while others rely on a separate web tool or USB application. In either case the gateway is the interface between the KNX project and the DALI bus state.
Q12
RGB control via KNX is typically performed with 3-byte colour telegrams (DPT 232.600).TrueFalse5. Lighting Control· Beleuchtung & Beschattung· MediumCorrect answerTrueLearning tipDPT 232.600 packs the red, green and blue components into a single 3-byte structure, each component scaled from 0 to 255. A single Group Address therefore carries the complete colour setpoint, which keeps the three channels synchronised and avoids the colour drift that occurs when R, G and B are updated independently. KNX visualisations and colour pickers natively serialise their output into this DPT.
Q13
Window contacts in a room can switch the HVAC system to frost protection mode through a KNX logic link.TrueFalse4. HVAC Control· HLK & Energie· MediumCorrect answerTrueLearning tipWhen a window contact reports 'open', it is standard practice to drive the room controller's HVAC mode object (DPT 20.102) to Frost/Heat protection, or to force its setpoint down to the frost protection value. The link is usually implemented either directly by parametrising the room controller or through a simple logic block that translates the 1-bit window state into the matching mode telegram. This avoids heating against an open window and protects pipes during winter ventilation.
Q14
Energy management in KNX can include load shedding in order to prevent grid overload during peak demand.TrueFalse11. Smart Metering· HLK & Energie· MediumCorrect answerTrueLearning tipLoad shedding logic monitors the measured total power (e.g. DPT 14.056) and, when a configured limit is approached, disables loads in a defined priority order (typically water heater, then auxiliary heating, then ventilation, then comfort outlets). Each load is wired to a priority/disable object and re-enabled when consumption drops below a hysteresis threshold. This avoids exceeding the contractual subscription or activating a peak tariff and is a standard energy-management feature on KNX.