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 ...

Relays continue to be useful and popular, but in low-power, battery operated applications they tend to be power wasters. The following relay economy circuits reduce coil power significantly by simply ...

A motor protection relay safeguards electric motors by detecting thermal stress, phase imbalance, stall, and abnormal ...

Overcurrent relays with inverse definite minimum time (IDMT) characteristics are widely used in power systems to protect ...

Protective relay testing verifies that installed relays will trip correctly under real fault conditions, confirming settings, ...

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 ...

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 ...

What is a relay? What is zero voltage switching? How to create a zero-crossing relay driver with a simple external circuit. A relay is a device that allows for a smaller electronic switch to control a ...

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 ...