Relay Form-A, Form-B, Form-C

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Relay Form-A, Form-B, Form-C

Post by vedard »

Relay is an electrical control device. When the change of the input (excitation) meets the requirements, the electrical output circuit will make the controlled circuit changing as predetermined. It has the interaction between the control system (also known as the input loop) and the controlled system (also known as the output loop). It is usually used in automated control circuits, and works as an "automatic switch" that USES a small current to control the operation of a large current.Therefore, it plays a role of automatic adjustment, safety protection and switching circuit in the circuit.

FORM-A, FORM-B and FORM-C are the relay models, FORM-C is conversion type and has normally open and normally closed contacts; FORM-A normally open has only normally open contacts. FORM-B normally closed has only normally closed contacts.
[attachment=1]double poles relay.png[/attachment]
[attachment=0]single pole relay.png[/attachment]
single pole relay.png
single pole relay.png (107.41 KiB) Viewed 1680 times
Relay contact NC NO security alarm
Relay contact NC NO security alarm
double poles relay.png (54.02 KiB) Viewed 1680 times
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