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.

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 ...

High voltage relays are electromechanical devices used to switch high voltage (> 1kV) signals. They operate using the same basic principles as electromechanical relays, but include features designed ...

Protective relays and monitoring relays detect or monitor for abnormal power system conditions. Protective relays detect defective lines, defective apparatuses, or other power system conditions of an ...

Over the years, control relays of various types have been used by the hundreds — even thousands — to control nearly every function in commercial and industrial processes. Today, many of those ...

When voltage sags occur inside or outside of a facility, properly placed power quality mitigation technology will save sensitive equipment from costly shutdowns. The cost of this mitigation equipment ...

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 ...

As automation expands, mechanical functions are relying more and more on electronic control. Solenoids provide an electromechanical interface for many of these applications. In addition, many ...

Sometimes, the most unexpected detours lead to the most interesting discoveries. After a brief break, I found myself revisiting latching relays—not just as components, but as puzzles waiting to be ...

Recently, [Manuel] did a post on making logic gates out of anything. He mentioned a site about relay logic. While it is true that you can build logic gates using switch logic (that is, two switches in ...

Reed relays contain a reed switch, a coil for creating a magnetic field, an optional diode for handling back EMF from the coil, and an encapsulating package with connection terminals. In many ways, a ...