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What exactly is a relay?
Relays are switches that open and close circuits electromechanically or electronically. Relays control one electrical circuit by opening and closing contacts in another circuit. As relay diagrams show, when a relay contact is normally open (NO), there is an open contact when the relay is not energized.
What is a relay classified as?
Basically, a relay is a device with contacts that opens and closes a switch as the result of an input signal (voltage or current) applied to a coil. Classification of relay can be mainly into two types: mechanical relays and solid state relays.
What does the Dictionary say about a relay?
Dictionary says that relay means the act of passing something from one thing to another, the same meaning can be applied to this device because the signal received from one side of the device controls the switching operation on the other side.
What are the different types of contact in a relay?
Change-over (CO), or double-throw (DT), contacts control two circuits: one normally-open contact and one normally-closed contact with a common terminal. It is also called a Form C contact or “transfer” contact (“break before make”). If this type of contact utilizes a “make before break” functionality, then it is called a Form D contact.
How are electrical relays different from mechanical relays?
This type of relay has contacts that are mechanically actuated to open/close by a magnetic force to switch signals, currents and voltages ON or OFF. Unlike mechanical relays, this type of relay has no moving contacts but instead employs semiconductor and electrical switching elements such as triac and MOS FET.
How are relays used in a computer circuit?
1 Relays are not only used in the large electrical circuits but also used in computer circuits in order to perform the arithmetic and mathematical operations in it. 2 Used to control the electric motor switches. 3 Automatic stabilizers are one of its applications where a relay is used.