The Working Principle Of Electromagnetic Relay

The electromagnetic relay is one of the earliest types of relays and the most common type of relay on the market. The electromagnetic relay is composed of seven components: electromagnetic coil, iron core, armature, contact, return spring, bracket and pin.
So how does the electromagnetic relay work?
In fact, the working principle of electromagnetic relay mainly depends on the principle of electromagnetic induction. When current acts on the coil, the coil generates a magnetic field, and the iron core under the coil is magnetized to generate magnetic force, so the armature is attracted to the iron core under the action of electromagnetic gravity. At this time, the armature drives the support rod to push the leaf spring away, thereby disconnecting the two normally closed contacts. When the current of the relay coil is disconnected, the iron core loses its magnetism, the armature returns to the initial state under the action of the leaf spring, and the contacts close again. There are three types of relay contacts as follows:
The first is a static contact that is in a conducting state when the relay coil is not energized, called a normally closed contact, represented by the letter H.
The second type is a static contact in the open state, called a normally open contact, represented by the letter D:.
The last one is that the movable contact and the static contact are normally closed, and at the same time they are normally open with the static contact, forming a switch contact form, represented by letters. When the coil is energized, the normally closed contact reopens through the closed state, so it is also called a dynamic breaking contact, and the normally open contact is called a dynamic closing contact. Switch contacts and relays can have OR.
Multiple (groups) normally open points, normally closed contacts and corresponding transfer contacts.