Thanks all, for your advice
I found Kemppis address and emailed them,
I got a reply back in a few hours, I'm impressed with their aftersales
service (even if it wasn't what I wanted to hear)

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From the rating plate on this machine, the mains supply is norminal value is
1phase 230v ( 198v - 254v)
the rated fuse is 16amp slow blow
The input current is proportional to the output value set on the current
dial.

At max output the power is 6200 VA (6.2Kva) power factor 0.75 therefore
output power in watts is 8267 watts
At 75 amps output the power is 2900 VA so an estimate of power in watts (pf
approx 0.6) is 4833 watts

Therefore we would NOT recommend using your battery/inverter supply to power
this equipment
because of the in-rush and surge currents even at the low output and using
1.6mm electrodes.

The generator supply is probably also not large enough, unless it has a very
well regulated output, again due to
the in-rush and surge currents even at the low output and using 1.6mm
electrodes.

We recommend a minimum generator of 6.2Kva.

Best Regards
Martin Forster
Service Technician

Kemppi UK Ltd
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