Question

How do I choose between a Normally Open (NO) and Normally Closed (NC) sensor ouput?

Answer

Normally Open sensors do not pass power to the PLC until an object is detected. Normally Closed sensors always pass power to the PLC until an object is detected. The majority of AutomationDirect sensors have Normally Open outputs, however, there are many sensors available with Normally Closed outputs as well.

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FAQ Subcategory: None

This item was last updated on 2021-02-10
Document ID: 460

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