How to test the quality of inverter

There are three steps to test an inverter that you don’t know whether it is good or bad.

The first step is static testing (no power), use the 1K position of the pointer multimeter to measure the main circuit of the inverter. The main circuit includes the AC input power supply part, the AC rectifier to DC and then the filtering circuit, which also has a buffer current limiting circuit, and then the inverter circuit. The measurement method is to use the red test lead to connect the P end of the inverter DC power supply, and the black test lead to measure the input terminals R, S, T and output terminals U, V, W of the inverter in turn. The measured resistance value is about 5K, which is normal. Then connect the black test lead to the N end of the inverter DC power supply, and the red test lead to measure the R, S, T, and U, V, W of the inverter in turn. The measured resistance value is also about 5K, which means the main circuit of the inverter is basically normal.

The second step is the no-load test. Power on the inverter to see if the inverter can perform self-check. If it does not report a fault and the standby state is normal, you can then perform a no-load test.

The third step is load testing, which is mainly to detect whether the inverter has any hidden faults. This test requires the inverter to run for a while with load.