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 ...

FIGURE 1: This electrical schematic diagram shows the cooler’s single-phase, R-134a capacitor start/capacitor run (CSCR) refrigeration compressor motor, and starting relay circuit section. July 6, ...

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 ...

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 ...

Working on car electrical stuff is a lot easier when the relay's schematic diagram is stamped into the metal of the case. My collection of relays is mostly Japanese, since the German ones get used up ...