Question

In the sequence for checking a KNX installation, which check is carried out immediately after checking the polarity of all bus devices?

KNX BasicLearnKNX InstallationMedium
Answer

C — Measuring the bus voltage at each bus cable end

Correct: The polarity check is followed by measuring the bus voltage (minimum 21 V) at each bus cable end.

Source

KNX Basic Course Documentation — 17 — p. 118

All proposed choices (exam context)
  1. A.Measuring the insulation resistance of the bus cables
  2. B.The visual check of the bus cable-end marking
  3. C.Measuring the bus voltage at each bus cable end
  4. D.Recording the test results
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Last updated: 19 May 2026

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