Common Faults of Inverter-8
There is frequency display, but no voltage output:
1. After the inverter is running, there is running frequency, but there is no voltage output between U, V, and W. At this time, it is necessary to check whether the carrier frequency parameter is lost.
2. If the carrier frequency parameter is normal, run the frequency converter and use an oscilloscope to check whether its drive waveform is normal.
3. If the driving waveform is abnormal, check whether the SPWM waveform sent by the CPU of the main control board is normal. If it is abnormal, the CPU is faulty; If the driving waveform of the driving board is still abnormal, the driving circuit part is faulty and needs to be repaired or replaced.
The relay does not pull in:
1. First, check whether the input power supply is abnormal (if not equal).
2. Check whether the connection between the power board and the capacitor board is correct and whether there is any looseness.
3. Check whether the 26P cable between the main control board and the power board has poor contact or disconnection, which will cause the REC control signal to be invalid and the relay not to close.
4. The components of the relay pull-in circuit are broken, which also causes the relay not to pull in.
5. The interior of the relay is broken (such as coil disconnection, etc.).
