Which statement correctly contrasts normally open and normally closed contacts?

• A. Normally Open means the circuit is closed when inactive; Normally Closed means the circuit is closed when inactive.
• B. Normally Open means the circuit is always closed; Normally Closed means always open.
• C. Normally Open means the circuit is open when inactive; Normally Closed means the circuit is closed when inactive.
• D. Both terms describe a closed circuit in all conditions.

Answer: (C)

The key idea is how a relay or switch behaves when nothing is happening to it (inactive). A normally open contact has a gap in the circuit at rest, so the circuit is open until the actuator energizes and closes the contact. A normally closed contact, on the other hand, is completed at rest, so current flows until the actuator opens it.

So the correct description states that the circuit is open when inactive for a normally open contact, and the circuit is closed when inactive for a normally closed contact. This matches how these contacts behave in real circuits, where actuation changes the connection state. The other statements describe states that don’t align with the default open or closed conditions.