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Safety Relay: Positive Common Input

FAQ No. FAQ02416

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Question

What is a positive common input?

Answer

It is an input mode where there are two inputs and both of them are connected to the positive side of the power supply. Both inputs will be at the same voltage, so if there is a short circuit between two terminals, it will not be detected.

If there is the possibility of a short circuit at the input, do not use this input method because it cannot detect faults, and it cannot ensure safe operation.