Co-ordination of overvoltage and short-circuit protection for aircraft A-C systems

The purpose of a circuit protector (CP) is to clear faults and thus permit the remainder of the system to continue normal operation. The function of overvoltage protection is to prevent damage to utilization equipment by de-energizing the generator when system overvoltage exists. Proper co-ordination is necessary to prevent nuisance tripping of the overvoltage relay (OVR) during low-resistance faults.