A bistable relay is a unique type of relay that holds one of two stable states without requiring continuous power to maintain its position. It is often referred to as a “latching” relay due to its ability to “latch” into a particular state, either energized or de-energized, until an external signal prompts a change. Unlike conventional relays, which require a continuous flow of current to hold the relay in one state, bistable relays provide significant advantages in terms of energy efficiency and long-term reliability.

Working Principle The working principle of a bistable relay revolves around its ability to switch between two stable positions using electrical impulses. These relays typically consist of a coil, contacts, and a mechanism that enables them to “latch” into either position. When a pulse of current is applied to the coil, the relay’s internal mechanism switches to the opposite state. Once the pulse is removed, the relay remains in its new state until another pulse is applied to switch it back. A key difference between bistable and traditional relays is that the bistable relay does not need a continuous supply of current to keep its contacts in a particular position. Instead, it only requires power during the switching process, which allows for energy savings and less heat generation.