The utility model relates to a low pressure alternating current switch break -make inspection power factor test system comprises basic circuit and characteristic circuit, and characteristics lie in: the characteristic circuit includes that PLC still distinguishes the electricity and connects isolating amplifier circuit A, isolating amplifier circuit B, DSP, isolating amplifier circuit A electricity connection preceding stage load impedance and IGBT array A, and electric back level load impedance and the IGBT array B of connecting of isolating amplifier circuit B, DSP pass through current detection module, the voltage testing difference is electric connects by inspection low pressure alternating current switch. Its test method is disclosed simultaneously. Having realized power factor intelligent test, mainly having replaced eadie plotting eadie, additional power supply method or dc component method, test procedure is simple, the test specification is big, the measuring accuracy is high,the test result deviation is small, replaces disconnecting switch manual switching load impedance, easy operation, automatic competent, good reliability.