Abstract:mainly according to the standard of GB/T5576-2008 low voltage complete sets of reactive power compensate device, this article introduces the test method and principle of dynamic response time detection project. It introduces and analyses the failure which would happen in the test process, such as compensation does not reach the design value. Making the Use of shavings cove coil to gather the time parameter of compensated current waveform, and making the use of SP controller to control the conduction time and stop of distribution line load end. Through the analysis of introduction, we can improve the test efficiency of this project detection.