I have a problem with Mitsubishi f700 22kW [ fr-f740-00470-ec] VFD. When it arrived to our workshop, there was a short circuit between the rectifier outputs. I disassembled it and found there is a carbon deposit between the DC Bus outputs. The IGBT module and the caps were good. After cleaning the carbon it off, I reassembled it.
I tested with a 400v transformer by giving power to two terminals L1 and L2. But now there is a CPU error E.7
According to the manual the fault is "CPU fault - Stops the inverter output if the communication fault of the built-in CPU occurs.
Check point Check for devices producing excess electrical noises around the inverter. "
How would I be able to solve this ? Please help.
I tested with a 400v transformer by giving power to two terminals L1 and L2. But now there is a CPU error E.7
According to the manual the fault is "CPU fault - Stops the inverter output if the communication fault of the built-in CPU occurs.
Check point Check for devices producing excess electrical noises around the inverter. "
How would I be able to solve this ? Please help.