What does a relay switch do?
Relays are electric switches that use electromagnetism to convert small electrical current into larger currents. These conversions occur when electrical inputs activate electromagnets to either form or break existing circuits.
A relay switch may be used in circuits where it is not possible to have a direct electrical connection between the control circuit and the electrical components. A relay is a special type of switch turned on and off by an electromagnet. When a current flows through the coil, an electromagnetic field is set up.
What is the difference between switch and relay?
They both serve the same function, i.e., opening or closing a set of contacts to control an electrical device. Switches are manually actuated by the user. Relays are controlled by energizing an electromagnet, which in turn causes the contacts to open/close.
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