Finder intermediate relay is used in relay protection and automatic control system to increase the number and capacity of contacts. It is used to transmit intermediate signals in the control circuit. The structure and principle of finder intermediate relay are basically the same as that of AC contactor. The main difference between finder intermediate relay and contactor is that the main contact of contactor can pass through large current, while the contact of finder intermediate relay can only pass through small current. So it can only be used in the control circuit. Generally, there is no main contact, because the overload capacity is relatively small. Therefore, it uses a large number of auxiliary contacts.
Principle of finder intermediate relay
When the coil is energized, the moving iron core moves and closes under the action of electromagnetic force, and the moving contact moves to separate the normally closed contact and close the normally open contact; When the coil is powered off, the moving iron core drives the moving contact to reset under the action of spring. The working principle of the relay is to make it act to a predetermined value when a certain input quantity (such as voltage, current, temperature, speed, pressure, etc.), so as to change the working state of the control circuit, so as to achieve the established purpose of control or protection. In this process, the relay mainly plays the role of transmitting signals.
Part of finder intermediate relay
Finder intermediate relay is a kind of relay. Its principle is the same as that of AC contactor. It is composed of fixed iron core, moving iron core, spring, moving contact, fixed contact, coil, wiring terminal and shell.