A bistable relay, also known as a latching relay, is an electromechanical device that has two stable states. Unlike a standard relay that requires continuous power to maintain its position, a bistable relay can remain in either of its two states without consuming power. This unique characteristic makes it particularly valuable in various electronic and electrical applications where power efficiency and reliability are essential.

How Does a Bistable Relay Work? A bistable relay operates using an electromagnetic mechanism, similar to a conventional relay, but with a crucial difference in its design. It uses a permanent magnet or a spring-loaded mechanism to hold its position after being actuated. The relay consists of a coil, which, when energized, causes a plunger to move and either make or break a contact. When the coil is de-energized, the relay stays in its new state without requiring continuous power. A bistable relay typically has two coils—one for setting the relay to its ON state and another for resetting it to its OFF state.