Design and Development of a Secondary Relay Testing Kit

Abstract

A Secondary Relay Testing Kit is a portable device used to test and verify the performance of protective relays in electrical power systems. The kit injects a controlled current or voltage into the relay circuit to simulate fault conditions without disturbing the main power system. It is mainly used for testing overcurrent, overvoltage, undervoltage, earth fault, and other protection relays.

The testing kit generally consists of a variable current source, voltage source, digital ammeter, voltmeter, timer, and protection circuits. During testing, the relay is disconnected from the actual CT or VT secondary circuit and connected to the kit. The relay response, tripping time, and operating characteristics are then measured accurately.