The Design And Implementation Of Low Voltage Leakage Protector Tester

Low voltage circuit breaker and low voltage leakage protector is the most used electricalequipment in low voltage distribution network, its reliability and stability directly affect thenormal operation of the whole distribution system. Low voltage circuit breaker has protectionfunction with the condition--overload, short circuit, and under voltage. Low voltage leakageprotector not only has that function, but also has the electric leakage protection function. Forconvenience, both will be collectively referred to as low voltage protector. Low voltageprotector will be used after the manufacturers’ test. In using process the protector’s life will bereduced due to the factors such as aging or poor contact terminals.Tripping characteristics and sensitivity is the most important feature of low voltageprotector, they show the mechanical properties and electrical properties of low voltageprotector. In case of leakage, overload or short circuit phenomenon in power distributionsystem, abnormal tripping characteristics not only can bring hidden danger to the equipment,also may cause electrical fire or electric shock accident.The simulated load for tripping characteristics of protector is designed, which based onIGBT chopper circuit. Compared with the traditional simulated load, it is characterized bylarge current, high power. I designed the leakage current simulated load, which is based ondigital potentiometer, characterized by digital adjustable. Using the Silicon Labs company’sC8051F020as the microcontroller, Cirrus Logic company’s CS5460A as the powermeasurement chip. On this basis, I designed algorithms for the measurement of voltage,current, active power, action time, waveform display and wrote the corresponding C languageprogram. Some problems encountered in the design process are discussed, correspondingsolutions are given.