Question

Is it possible to wire multiple safety switches in series to the e-stop/safety gate safety relay inputs?

Answer

In the cases where the safety input circuit forms a loop (terminal S11 - S12 and S21 - S22), the total voltage drop in that circuit should not exceed 2 Vdc, which at 30mA sensing current, allows for 60 ohms maximum resistance.

Also, there may be repercussions to the Safety Integrity Level of the overall system that would fall under the customer's responsibility to determine.

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FAQ Subcategory: None

This item was last updated on 2011-05-18
Document ID: 1372

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