To clarify, I pulled 1kWh at around 200W (16 amps at 12v) through my small grid tie inverter- it took all night! The traction battery was the source of energy, topping up my auxiliary battery when needed.
OK, to answer the 100A draw question - I just went and tested the max continuous current draw from the user installed aux 45Ah 12V battery pack when supported by the traction battery.
I connected my 1000W 240V Inverter and used a hairdryer with different fan and heat settings as my test load.
Using a power meter, I found that in the 240v side I could easily sustain about 570Watts without the system overheating. The power was coming from the traction battery, as the isolator was indicating the 12v factory installed battery as full all the time, and the S.O.C .meter on the aux battery pack was continuously reading 100%. This means the PHEV was holding the 12V battery supply at 14.4 volts, and supplying all of the current.
However, the inverter shutdown for power settings over 1100 watts, so I can't confirm any higher power draw at the moment.
570W would easily run a domestic fridge.
TL;DR
50A draw at 12v tested for about 15 minutes with no apparent problem.
100A needs more testing. I'll get back to you.
**Update
After upgrading some 50A cables from to 115A I ran another test, this time using a 240v vacuum cleaner, which gives a continuous range of wattages.
Turns out the maximum wattage supported is 760W (63A @12v); the inverter shuts down not due to low voltage, but insufficient current.
I suspect that the PHEV inverter limits current to the starter battery to around 75 amps (considering 240v inverter losses), so as not to damage it with too high a charging current.
Anyway, the system could sustain 760W although the cables did become worryingly warm, and the connectors on the Projecta isolator where hot to touch - not good.
The 100A isolator is rated at 12V 75A continuous draw; so I think it was running above capacity if there was 63A on the 240v side, since efficiency is probably lower than 15%.
I left the system running @ 500W for about 2 hours until the power meter indicated 1kWh was drawn. The traction battery meter on the dash had dropped a bar.
In summary;
500W @ 240V draw is sustainable. (estimated 50A @12V). Lights, fridge, charging electronics could be done indefinitely.
760W @ 240V runs the system hot; PHEV appears to shut off supply to starter battery above this wattage. (estimated 75A @12V).
Upgrading the isolator to 150A and all the DC cables to 115A would probably allow continuous 760W draw.
Hope this helps.
