A simple and convenient way to interface 2 relays for switching application in your project. This relay driver boosts the input impedance with a regular BC547 NPN transistor (or equivalent). Very ...

The real core of engineering, in addition to technical expertise, is the ability to articulate the inevitable tradeoffs and pros/cons of design alternatives, and then weigh these relative to each ...

Relays usually are driven using optocouplers, which offer isolation between analog and digital grounds to ensure that switching currents in the relay coils do not affect the noise margin of the ...

As an electric motor’s rotor turns in close proximity to the motor windings, a bucking voltage or back electromotive force (EMF) is generated. The back EMF (BEMF) generated across the start winding is ...

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 ...

Last column, I wrote about various applications where fire alarm relays could be used to integrate a commercial fire alarm system with other electrical systems at a customer’s site to provide them ...