A relay is an electronically operated switch that is remotely activated by an electromagnet which pulls a set of contacts to either make or break a circuit. Relays are commonly used for switching signals, radio frequencies, high current circuits when using a lower current circuit, and loads such as resistive, motor, lamp, inductive, and capacitive applications. This is helpful when an in-line switch or existing circuit does not have the capacity to handle the required current.


Types of Relays：
Electromechanical Relays (EMRs) and Solid State Relays (SSRs)

Functions of Relays：
● Galvanic separation of the primary or actuating circuit and load circuits
● Single-input/multiple-output capability
● Separation of different load circuits for multi-pole relays
● Separation of AC and DC circuits
● Interface between electronic and power circuits
● Multiple switching operations – time delay, signal condition, among others
● Serves as an amplifier