Relays and contactors use a variety of technologies to switch signals and power connections. Many devices called relays use similar techniques and topologies, but the terminology can be confusing.

Coil hold-in devices were created specifically to solve the voltage sag problem with control relays and contactor/motor starters. There are two designs of low-cost coil hold-in devices available. Both ...

A contactor is just a heavy-duty mechanical relay for switching high voltages or high currents, or both. A common application is the contactor in every car and truck that starts the engine.