What does NC stand for in relay terminology?

What does NC stand for in relay terminology?

• A. Normally Closed
• B. Normally Open
• C. No Connection
• D. Neutral Connection

Answer: (A)

NC stands for Normally Closed. In relay terminology, “normally” refers to the coil’s de-energized state. A normally closed contact is closed (conducts) when the coil is not energized, allowing current to flow. When the coil is energized, the contact opens and stops the current. This default-on behavior is useful for safety and fail-safe designs, where power or signal is maintained unless intentionally interrupted. For contrast, a normally open contact is open when the coil is de-energized and only closes when energized. The other terms—no connection and neutral connection—are not standard ways to describe relay contact states.

NC stands for Normally Closed. In relay terminology, “normally” refers to the coil’s de-energized state. A normally closed contact is closed (conducts) when the coil is not energized, allowing current to flow. When the coil is energized, the contact opens and stops the current. This default-on behavior is useful for safety and fail-safe designs, where power or signal is maintained unless intentionally interrupted. For contrast, a normally open contact is open when the coil is de-energized and only closes when energized. The other terms—no connection and neutral connection—are not standard ways to describe relay contact states.