Working Of Relay Pdf

Post navigation

The switching mechanism is carried out with the help of the electromagnet. Thus the upper contact arm starts to be attracted to the lower fixed arm and thus closes the contacts causing a short circuit for the power to the load. Working of Contactors Types of Relays.

The reluctance of the magnetic path is kept minimum for making the circuit more efficient. You must note some factors while selecting a particular relay. Circuit Globe Switchgear and Protection Relay.

Working Principle of Relay

Such relays are called contactors. An iron core is surrounded by a control coil. Your email address will not be published.

The good contact gives limited contact resistance and reduced contact wear. Electronic Instrumentation. Its very helpfull for training.

We know that most of the high end industrial application devices have relays for their effective working. Relays have the exact working of a switch. Thus the switch plays an important role in the relay working. Relays consist of an electromagnet and also a set of contacts.

Thus the switches remain open. As it is a part of the load circuit, it is used to control an electrical circuit that is connected to it.

Overload relays are installed in motors to safeguard against sudden current spikes that may damage the motor. In this article, the basics of a relay like energized relay and de-energized relay are explained in detail. The contact between the strip and the contactor causes the contactor to de-energize and restricts the power to the motor, qu est ce qu un document pdf and thus turns it off.

Relays are simple switches which are operated both electrically and mechanically. This strip is set to make contact with a contactor by bending itself with rising temperatures due to excess current flow.

Need more detailed diagrams. After the invention of computers they were also used to perform Boolean and other logical operations.

The most widely used overload relay is the thermal overload relay where a bimetallic strip is used to turn off the motor. The multi-ball bearing provides low friction and greater resistance to shock.

The small power relay has only one contacts, and the high power relay has two contacts for opening the switch. Thus the relay becomes de-energized and thus in off position.

The fixed contacts are usually spot welded on the terminal link. For low voltage applications, more preference will be given to reduce the noise of the whole circuit. It works on the principle of an electromagnetic attraction. They were also used in long distance telegraphy.

Relay Working

Working of relay pdf

It consists electromagnetic and sets of contacts which perform the operation of the switching. So thank you for your fine post which is very helpful! The construction of relay is mainly classified into four groups.

Very safety without delay work. It has an iron core which is wound by a control coil.

Similarly, the single pole double throw relay has a one switch and two possible connections. The green colour represents the control circuit and the red colour represents the load circuit.

Share This Post

Working of relay pdf

All overload relays available to buy comes in different specifications, the most important of them being the current ranges and response time. If the contact is already closed, then it moves oppositely and hence open the contacts.

The current flows through the coil produces the magnetic field around it. The single ball bearing is used for high sensitivity and low friction. So, the same concept is also applied.