203694 ⎘
Protective switches, e.g. circuit-breaking switches, or protective relays operated by abnormal electrical conditions otherwise than solely by excess current operated by abnormal product of, or abnormal phase angle between, voltage and current, e.g. directional relay
PROTECTION THROUGH A POWER TRANSFORMER USING COMPENSATED VOLTAGES AND CURRENTS
#2Crowbar device and multistage crowbar apparatus
#3Fuseless switch for cross phase of power line communication
#4Power distribution box equipped with resistive leakage current detector
#5Electric power generation control system for vehicle