DEVICE FOR PROTECTING THREE-PHASE LOADS AGAINST PHASE-FAILURE AND ASYMMETRIC MODES OF OPERATION Russian patent published in 2003 - IPC

FIELD: electrical engineering; phase-failure and asymmetric-mode protective gear for three-phase loads. SUBSTANCE: device has magnetic starter one of whose coil leads is connected through START button to phase lead of supply mains and other one, to center tap of series-connected capacitor and resistor provided with inductive coil, all being connected to other phase leads of supply mains. Ratio of resistances of capacitor and inductance coil is 2 : 1 and that of resistances of resistor and inductance coil is START button is mechanically coupled with power contacts of electromagnetic starter at the moment of its closure. EFFECT: simplified design, enhanced reliability, and reduced power requirement of device. 1 cl, 1 dwg