Why won't 2000w inverter run 900w microwave?

MitchF150 wrote:
there are different reasons for needing to use the MW when 'off the grid', but even if you get it to work as you want, wouldn't that amount of power consumption basically drain the battery bank of power?? Won't you have to recharge it in some manner?
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Hope you are able to resolve your issue, but for me, I'd just find another mode to cook with... ;)

In their case - 40 seconds reheating - it won't drain the battery. Reheating one bowl of food for an adult from 40F to hot takes 3-4 minutes on an average microwave. And this would still not drain the battery too much, though would cost you about 12 amp-hours considering higher than normal depletion at high currents (Peukert effect). Do it twice a day and you are 48 AH off, by the end of the 2nd day. With 2 6v batts they have 225 AH of usable 12V energy, so 48 AH is a lot, but still doable. They probably need to run a generator on the 2nd day. Like others said, MW current is too high for 2*6V batts, they will die soon, doesn't matter how frequent you charge them.

Yes, there are other modes to cook, without microwave and generator. Most of those modes are not "automated", you need to pay attention to what you are doing. Reheating on gas stove without adding fats can be done in a double boiler, aka Baine Marie. Like those for melting chocolate or making candles. They are cheap, but it takes 5-10 minutes for water to heat up before the heat begins transferring to the food. If you are in a hurry, microwave is the only choice. Why people are in a hurry when camping, is beyond my understanding though.

This all still doesn't answer "our" questions ;)... Could be a faulty MW, AC line, DC wires, faulty inverter, faulty batteries. They have to check everything. Yes, 700W microwave could help, taking some stress off the system, so they could make it work without finding the problem.