Relay works

Electromagnetic relays generally core, coil, armature, composed of reed contacts. As long as the voltage across the coil with a coil in a constant current will flow through, thereby generating electromagnetic effects, the armature will be attracted by the electromagnetic force of the return spring to overcome the effect of the suction force to the core, so as to drive the armature dynamic contact with the stationary contact (normally open contact) pull. When the coil power, the electromagnetic suction disappeared, the reaction force of the spring armature will return to the original position, so that the moving contact with the original stationary contact (normally closed contact) released. This pull, release, so as to achieve conduction in the circuit, the purpose of cutting. For the relay "normally open, normally closed" contact, it can be distinguished: the relay coil is not energized stationary contact in a disconnected state, known as the "normally open contact"; in the ON state, said stationary contact is "normally closed contact." Relay circuits generally have two shares for low voltage control circuits and high voltage operating circuit.