ANORDNING FOR FELINDIKERING VID ROTERANDE ELEKTRISKA MASKINER

摘要

Electrical potentials are induced in the rotating shaft of many rotary electrical machines because of stray flux that exists in the machines. Unless provided with adequate ground insulation to interrupt the circuit, currents can flow through the machine bearings and other parts to ground and thereby expose the machine to severe damage. The device of this invention measures the voltage across the shaft and the bearing to indicate if there is a circuit for excessive current leakage from the bearing to ground.