Which statement about limit switch contacts is true?

• A. Limit switches do not have NO or NC configurations
• B. Normally Open contacts close on actuation
• C. Normally Closed contacts open on actuation
• D. Normally Open contacts close on actuation, Normally Closed contacts open on actuation

Answer: (D)

Limit switches use two kinds of contacts: normally open and normally closed. In the resting state, a normally open contact is open (no current flows), while a normally closed contact is closed (current can flow). When the actuator is triggered, the normally open contact closes and the normally closed contact opens. This behavior—NO contacts closing on actuation and NC contacts opening on actuation—is why that statement is true. It also explains why limit switches commonly provide both types of contacts to suit different control needs. The other options are incorrect because limit switches do include NO and NC configurations, and the complete behavior involves both actions on actuation, not just one part of it.