This chapter covers representative general-purpose relays used in the control circuits of most industrial, commercial, and consumer products. Relay names and terminology are in accordance with ...

This file type includes high resolution graphics and schematics when applicable. According to the research firm IHS Inc., about 54 million relays and timers were purchased in 2013, a number projected ...

Ladder logic uses switch or relay contacts to implement Boolean expressions. In years past, ladder logic was made possible with discrete relays and was sometimes termed “relay logic.” Today most ...

Have you ever needed to power a 12-volt relay in a circuit but only had 6 or 9 volts available? This simple circuit will solve that problem. It allows 12-volt relays to be operated from 6 or 9 volts, ...

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 ...

Potential relays are commonly found on many smaller, single-phase, capacitor-start, capacitor-run motors in the HVACR industry. Their function is to assist in starting the electric motor. Potential ...

Relays are clunky, switch slowly, have contact bounce, and make noise, both acoustically and electromagnetically, so why are they still used? Relays are clunky, switch slowly, have contact bounce, and ...

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 ...

According to a Tyco Electronics application note, “Silver cadmium oxide contacts have long been used for switching loads that produce a high energy arc. Silver cadmium oxide contacts are less ...