Relays are electromechanical devices that use a magnetic solenoid to actual a switch. When current is passed through the solenoid coil, it produces a magnetic field. The magnetic field is strengthened ...

Testing relays is both an art and a science. As relay technicians inevitably learn in the field, pure theory-based understanding of protective relays is not nearly enough for the real-world situations ...

Ideally a test engineer would connect a separate instrument to each test point of a Device Undergoing Test (DUT), thereby providing the highest performance and most accurate measurements. But this is ...

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.

The reed relay was invented in 1936 by Bell Telephone Laboratories. Since that time, it has gradually evolved from very large, relatively crude parts to the small, ultra-reliable parts we have today.

The Barrington Model Circuit Breaker Simulator was designed to be a convenient, lightweight alternative to operating high-voltage circuit breakers while testing the operation of substation protection ...