Logic Circuit-relay

Relay

Electromagnetic relay is generally composed of core, coil, armature, contacts Reed, etc. As long as a certain voltage is added to both ends of the coil, the coil will flow through a certain amount of current, resulting in electromagnetic effect, the armature will overcome the pull force of the return spring under the action of the electromagnetic force to suck to the core, so as to drive the dynamic contact and static contact (normally open contact) of the armature to suck. When the coil is powered off, the electromagnetic suction will also disappear, and the armature will return to the original position in the reverse force of the spring, so that the dynamic contact and the original static contact (normally closed contact) will be released. In this way, the transfer and disconnection in the circuit are achieved.

From (1) We can see that the control of the switch is controlled by the input current, which is a great improvement.

Figure (1)

 

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