Question
If several KNX TP devices transmit at the same time, which logical state prevails on the bus?
Answer
B — Logical 0, because a 0 draws current and overrides a 1
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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An error or unclear wording? Report this questionAll proposed choices (exam context)
- 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
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