Latching relays change their states when you apply a short voltage pulse to their coils. Because these relays require no continuous coil currents to keep their states, you can save considerable power ...

[Teodor] writes in with a unique Tesla coil he designed and built. Unlike most Tesla coils, [Teodor]’s design is able to run with a fairly low input voltage because it doesn’t use a static spark gap ...

An RC circuit in series with the coil allows full-current turn-on for reliable relay operation, then reduces the current to save power. Fellow engineer Sanjay R. Chendvankar of Mumbai, India, recently ...

Some relays will become warm if they remain energized for some time. The circuit shown here will actuate the relay as before but then reduce the ‘hold’ current through the relay coil current by about ...

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.

Relays are electromechanical devices that use a magnetic solenoid to actual a switch. When current is passed through the solenoid coil, it produces a magnetic field. The magnetic field is strengthened ...