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 ...

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 ...

Cooper Power Systems has designed its full-featured differential relay, the iXP-420, to provide comprehensive two-winding transformer protection, and monitoring and control. The iXP-420 incorporates ...

Nov. 13, 2008, PULLMAN, WA - Schweitzer Engineering Laboratories, Inc. (SEL) is now taking orders for two new products, the SEL-787 and SEL-487E Transformer Protection Relays. These are the first ...

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.