What type of switch is identified as Normally Closed?

• A. Limit Switch N.C.
• B. Timed Contact N.O.T.C.
• C. Pushbutton N.O.
• D. Float Switch N.O.

Answer: (A)

A Normally Closed switch is one that, in its default state (when not actively engaged), allows current to flow through it. This means that the circuit is complete until the switch is actuated or triggered, which then opens the circuit and stops the flow of electricity.

In the context of a Limit Switch N.C., it is designed specifically to be closed when the triggering condition is not met, making it ideal for applications where a default 'on' condition is necessary until a specific event occurs to change that state. This mechanism is commonly used in safety systems and machinery to ensure that operations happen under controlled conditions.

Other types of switches listed do not fit the characteristics of a Normally Closed switch. For instance, Timed Contact switches, while they may involve a timing mechanism, do not inherently imply a normally closed position. Similarly, Pushbutton and Float switches mentioned are normally open, meaning they do not allow current to pass until they are actuated or the condition is met, which is contrary to the definition of a Normally Closed switch. Therefore, the Limit Switch N.C. is indeed the correct identification for a Normally Closed switch.