KNX exam questions: the real format, worked examples and a practice plan for panic week

Forget the four-bubble multiple-choice format you might expect from an IT certification. According to the exam regulations published by the KNX Association (support.knx.org), the KNX Basic theory exam is built from true/false statements — you read a claim about the KNX system and mark it True or False, typically via a radio button on screen or a paper answer sheet.

The mechanics, as documented by the KNX Association and accredited training centres

• Format: true/false statements, not classic 4-option MCQ. Every item on the paper is a claim you mark True or False.
• Session size: the exam regulations specify 100 statements per sitting. The individual statements are assembled for each session, but the count is fixed by the regulations.
• Duration: 1.5 hours for the theory exam, per the published regulations — comfortable if you know the material, tight if you are reading every statement twice.
• Delivery: either face-to-face on paper (an "offline" exam composed by the tutor) or through the KNX Association's own online exam tool at the training centre. Both use the same true/false statement bank logic.
• Administration: for the standard Basic course (minimum 30 hours of training), the theory and practical exams are conducted face-to-face in the presence of a KNX tutor — you cannot sit the theory exam unsupervised from home.

Why this matters for anyone hunting for "real exam questions" online: a PDF or flashcard deck built around four-option multiple choice is training you for a format that is not the one you will actually face. The statement style rewards a different reading habit — spotting the one wrong number or wrong direction in an otherwise-plausible sentence — which is exactly what the worked examples further down are built to drill.

This is the mechanic that surprises the most candidates, and the one that should shape how you answer every statement on exam day. Per the exam regulations published by the KNX Association, the theory exam uses asymmetric, negative-marking scoring: a correct statement earns a positive point, an incorrect statement costs 0.5 points, and a statement left blank costs nothing — it is simply not counted either way.

Why "just guess" is not the strategy it sounds like

On a pure coin-flip guess between True and False, the expected value of answering is 0.5 x (+1) + 0.5 x (-0.5) = +0.25 points — technically better than leaving the statement blank. But do not mistake that for a viable exam strategy: applied across an entire session, blind guessing nets an expected raw score around 25% of the maximum, well short of the pass threshold. The math rewards answering when you have even a partial, reasoned opinion; it does not reward answering when you have none. Treat every "I have absolutely no idea" statement as a candidate for leaving blank, and every "I'm 70% sure" statement as one worth answering.

The pass threshold

• The standard KNX Basic course (minimum 30 hours) requires a minimum of 50% of available marks on both the theory and the practical exam.
• Some condensed, practical-only course formats (aimed at candidates who already hold prior KNX theory training) list a 60% threshold instead.

Because the threshold depends on which course variant you are enrolled in, confirm the exact figure with your accredited training centre before exam day — do not assume the number a forum post quotes applies to your session.

Why CertifBus mirrors this exactly

Every mock exam on CertifBus uses the same +1 / -0.5 / 0 scoring: a correct answer scores a full point, a wrong answer costs half a point, and a blank answer costs nothing. It is the one detail generic quiz apps almost never replicate, and it is the detail that most changes how confidently you should click an answer under a countdown timer.

The KNX Basic curriculum collapses into a handful of recurring topic blocks. Below are two original example questions per block — written for this guide, not copied from any leaked paper or third-party deck — each with a worked explanation. The true/false items mirror the real paper's phrasing; the single-choice items drill the same numeric decision points you must resolve to judge a statement correctly.

Topology and bus devices

Q1 (true/false). "On a KNX TP line, a single unrepeated line segment can never contain more than 64 bus devices, even when line repeaters are added." — False. The 64-device limit applies to one *segment*. Adding up to 3 line repeaters splits a line into 4 segments, giving a theoretical maximum of 256 devices per line (255 usable, since address 0 is reserved). The statement's trap is the word "never" combined with "even when" — a classic way the exam tests whether you understand repeaters extend a line rather than being irrelevant to the device count.

Q2 (single choice). What is the maximum cable length permitted between any two bus devices on the same KNX TP line? A) 350 m B) 700 m C) 1000 m D) 350 m, but only from the power supply. — Answer: B. 700 m is the device-to-device limit; 1000 m is the total line length budget; 350 m is the device-to-power-supply limit (option D describes a real rule but answers the wrong question).

Telegrams and communication

Q1 (true/false). "A telegram addressed to a group address is only processed by the single bus device whose individual address matches the destination field." — False. Group addresses are, by design, a one-to-many mechanism: every device with that group address bound to a communication object processes the telegram. Individual addresses are used for point-to-point traffic such as programming and diagnostics, not for normal group communication.

Q2 (single choice). Which part of a KNX telegram tells a receiving device whether to treat it as a read request, a write command or a value response? A) The priority field B) The APCI (Application Protocol Control Information) C) The checksum byte D) The source individual address. — Answer: B. The APCI field encodes the service (GroupValueRead / GroupValueWrite / GroupValueResponse); priority governs bus arbitration, and the checksum only validates transmission integrity.

ETS6 project design

Q1 (true/false). "In ETS6, a device can be added directly to a project's topology view without first importing its product data from the KNX Online Catalogue or a manufacturer file." — False. ETS6 needs the product's data (application program, communication objects, parameters) before it can be placed and configured — you import the catalogue entry first, then drag the device onto a line.

Q2 (single choice). Which ETS6 view is used to assign an individual address to a device by dragging it onto a specific physical line? A) Group Monitor B) Bus Monitor C) Topology view D) Building view. — Answer: C. The Topology view represents lines, couplers and physical addressing; the Building view organises devices by room/floor for group-address planning, not addressing.

Group addresses and communication flags

Q1 (true/false). "A push-button's sending group object should have its Write flag enabled so that other devices on the bus can update its state." — False. A sending object needs Communication + Transmit (C-T) so it can put a telegram on the bus when pressed. Enabling Write on a sending object lets other devices overwrite it — the classic misconfiguration that creates feedback loops between a switch and an actuator status object.

Q2 (single choice). Which combination of the C R W T U flags is typical for a status-indicator object that must refresh its display whenever a bus telegram changes the underlying value? A) C-T only B) C-W-U C) C-R only D) T-U only. — Answer: B. Communication + Write + Update: Write lets the bus update the object, Update refreshes ETS's internal cache/display state, and neither Read nor Transmit is required for a pure indicator.

Installation and commissioning

Q1 (true/false). "A KNX device's application program can be downloaded successfully before its individual address has been assigned, as long as the device is physically connected to the bus." — False. ETS6 may appear to let this happen, but the device has no valid address for the bus to route to — download the individual address first, then the application program, every time.

Q2 (single choice). What is the maximum permitted cable distance between a KNX TP bus device and the line's power supply? A) 350 m B) 700 m C) 1000 m D) There is no defined limit. — Answer: A. 350 m is the device-to-power-supply limit, distinct from the 700 m device-to-device and 1000 m total-line-length figures tested in the topology block.

KNX Secure

Q1 (true/false). "KNX Data Secure authenticates and encrypts individual telegrams on the bus, using a device-specific key derived from the FDSK printed on the device's label." — True. The Factory Default Setup Key (FDSK) is entered into ETS during commissioning and underpins the per-device key used for AES-128 authentication and encryption of Data Secure telegrams.

Q2 (single choice). What does KNX IP Secure primarily protect? A) Telegrams travelling on a TP line B) KNXnet/IP traffic exchanged between IP routers C) The ETS6 project file stored on a laptop D) The individual address table. — Answer: B. IP Secure wraps KNXnet/IP communication between routers/interfaces in a secure tunnel; Data Secure is the mechanism that protects bus-level (TP) telegrams.

Search for "KNX exam questions and answers PDF" and you will find document-sharing uploads and flashcard decks with names like "KNX EXAM - Question and Answers - Telegrams" or "System Arguments" scattered across sites such as Scribd, PDFCoffee and third-party flashcard platforms. They are tempting the night before an exam. They are also a worse bet than they look.

Four concrete problems

• They date from the ETS4/ETS5 era. Screenshots, menu paths and even some numeric limits in these decks predate ETS6 and the post-2023 curriculum. A candidate who memorises an ETS4 screen layout loses time re-orienting during the practical, and may pick up outdated terminology on the theory exam.
• They skip KNX Secure entirely. Every Basic exam since 2023 includes Data Secure and IP Secure content. Decks copied from older leaked material simply do not cover it — you would be studying a curriculum that no longer matches the exam.
• They use the wrong question format. Most of these decks are built as four-option multiple choice, because that is the generic quiz-app template, not because that is how the real exam is structured. Practising the wrong format trains the wrong reading habit — see the section above on true/false statements.
• There is no scoring, no explanation, and no accountability for errors. A flashcard says "answer: A" with no worked reasoning and no way to flag a mistake. If the card is wrong — and errors are common in crowd-uploaded decks — you memorise the error with total confidence.

None of this means you should avoid practice questions. It means the practice questions need to be current, correctly scored, and explained — which is a different product than a PDF someone forwarded you in a WhatsApp group.

To be direct: nobody can legally hand you the real KNX Association exam paper, and no training provider — including CertifBus — should claim to. The KNX Association does not publish its exam bank, and reproducing leaked exam content would be a breach of its own exam regulations for training centres.

What a legitimate practice resource can do instead is build original questions that cover the same public KNX standard concepts — topology limits from ISO/IEC 14543-3 and EN 50090, group communication and telegram structure, ETS6 workflow, communication flags, installation rules, and KNX Secure — written independently, at a comparable difficulty, in the true/false style of the real exam (plus single-choice drills), then scored with the same negative-marking rule described above.

That is the model CertifBus uses: every KNX Basic and KNX Advanced question is written in-house, tagged to a topic block and a difficulty level, and shipped with a sourced explanation rather than a bare "correct answer" label. It will never be word-for-word identical to a real exam statement — that is by design, not a limitation — but it will train the same reasoning under the same scoring pressure, which is what actually transfers to exam day.

The practical test for any resource you consider, PDF or platform: does it tell you *why* an answer is correct, does it use the true/false format, and does it apply the -0.5 penalty for a wrong guess? If the answer to any of those is no, it is testing something other than the exam you are about to sit.

If you found this page because the exam is a matter of days away rather than weeks, here is a compressed plan that fits around panic-week reality.

Step 1 — Take the free quiz in Learn mode

Go to /en/knx-basic/learn: 10 questions, no sign-up, no email required. Learn mode reveals the explanation immediately after each answer, so you leave the session knowing exactly which of the six topic blocks above is your weak point — usually flags, topology numbers, or KNX Secure, in that order of frequency.

Step 2 — Retake it in Exam mode

Same 10 questions available at /en/knx-basic/exam, this time timed and scored with the real +1 / -0.5 / 0 rule, no explanations until the end. This is the closest free simulation of the actual pressure: a countdown, a statement, and a decision about whether to answer or leave it blank.

Step 3 — If you have more than a couple of days, unlock the full bank

The free set is 10 questions; the full KNX Basic bank is 240, covering every block in proportion to how the real exam weights it. Access starts at €9 for one month — enough for a focused final push — with a 19 € three-month option if your exam date has any uncertainty and a 29 € six-month option for longer preparation windows. See /en/pricing for the current plans.

Step 4 — Run at least two full-length timed mocks before exam day

Once you have access to the full bank, run sessions at the real exam's scale (up to 100 questions, matching a real sitting) under the timer. Review every wrong and every blank answer's explanation immediately afterward — that review is where the actual learning happens, not the quiz itself.

Step 5 — The night before: review, do not cram new material

Re-read your flagged weak-block explanations and the C R W T U flag combinations one more time. Do not start a new topic block the night before the exam — the negative-marking rule punishes shaky half-knowledge almost as much as no knowledge at all, so consolidating what you already know is worth more than a rushed first pass at something new.

If your search for "KNX exam questions" turned up this page but your actual course is KNX Advanced, the underlying exam mechanics published in the KNX exam regulations — true/false statements and the same +1 / -0.5 / 0 negative-marking rule — carry over. What changes is depth and scope.

Advanced-level statements go further into multi-line and multi-area topology design rather than single-line limits, push harder on ETS6 features such as project comparison and conditional links, add KNX IP backbone design as a first-class topic rather than a footnote, and expect a working understanding of KNX Secure deployment and key management rather than just recognising what Data Secure and IP Secure protect. The practical exam mirrors this: expect error-finding and telegram/device analysis exercises layered on top of the project-design task that dominates the Basic practical.

If you are not yet certain which exam you are preparing for, start with the Basic-level free quiz at /en/knx-basic/learn — every Advanced topic builds directly on the six Basic blocks covered above, so gaps there will resurface at Advanced level regardless. Once Basic is solid, the free Advanced quiz at /en/knx-advanced/learn is the equivalent no-sign-up starting point for the next certification.