what's different of SPST NO and SPST NC?

What's different of SPST NO and SPST NC?

SPST-NO:Single Pole Single Throw,Normally Open

Disgram  SPST-NO:

image.png


SPST-NC:Single Pole Single Throw,Normally Closed

Disgram  SPST-NC:

image.png

A relay is an electrical control device.It has an interactive relationship between the control system (also known as input loop) and the controlled system (also known as output loop).Usually used in automated control circuits, it is actually an "automatic switch" that USES a small current to control the operation of a large current.Therefore, it plays a role of automatic regulation, safety protection and conversion circuit in the circuit.