Chapter 6, Problem 1RQ

Explanation of Solution

Principle of an electromagnetic control relay:

• The working of an electromagnetic control relay is based on the principle of magnetic induction.
• It consists of an electromagnet or coil to switch contacts.
• When the coil is energized, the movable contacts in between the fixed contacts will swing and come in contact with the bottom fixed contact.
• This results in passing current through the coil of the relay.
• On the other hand, if the coil is de-energized, then the movable contact will be detached from the fixed contact and acts as an open circuit.
• Hence, no current will be passed through the relay.