falah demery
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falah demery reacted to Coulomb in Axpert vmii 5kva the battery internal 150 A fuse blown and still short all componentsFault code 09 means Bus Soft Start failure. Usually this means that the 400V bus is shorted, usually because two or more IGBTs have failed shorted. As Jadav mentioned above, this often damages gate driver components like resistors and diodes, sometimes also the isolating driver chips, which are 8 pin devices, often white in colour, but can also be black.
If you're getting repeated catastrophic failures like this, then it might not be worth repairing a second time. There has been a recent spate of VM II clones, and some seem to be very poor quality.
Switching power electronics like this is something of an art to design well, keeping inductance low, knowing where to place snubbers and what values to use. These circuits get hot, so it's important to choose components with long lifetimes, which will not be the cheapest parts.