- In a relay or switch, a contact pair that is closed in the resting state, and which is opened when energized. The contact pair consists of a stationary contact and a movable contact. A normally closed contact provides a complete circuit when not energized. This contrasts with a normally-open contact, in which the contact pair is open in the resting state. Its abbreviation is NC contact. Also called normally closed, break contact, or back contact.
- abbreviationNC contact