5 KVA inverters in parallel

[Justloadit]

Semiconductor tabs are isolated from the heat sink, which is earthed with a membrane for isolation.
These membranes are rated at 4KV, depending on their thickness.

There is no reason that there could be an iron filling trapped between the membrane and the semiconductor, which in time can pierce the membrane and cause a path way to earth.
There is also no reason that could protect an arc between the mounting screw, or tab to earth due to a surge, which then punctures the membrane and create a path to earth.
Now the devices are switching a DC source to create AC, but there is nothing to stop the arc from continuing on the DC side and creating havoc.

Of course what I have explained above is exceptional cases, which I have experienced before, but is protection not there for the exceptional cases for additional protection to users?

Your call.

[ians]

I Found this in a document from Victron.

"To safeguard against this issue, it is recommended to use long AC, cables of similar length. Always follow the
recommended cable lengths and thicknesses as listed in the product manual. Do not increase the cross-section
of the AC cabling more than is recommended in the manual!"


"AC fusing parallel strings
For units in parallel it is advised to use one AC fuse for all units on that phase. Both on the input, and on the
output. Multiple fuses which are mechanically connected are okay to be used, this is counted as one fuse"