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I found this online, talking about inverters:
Cheapies, ie 500-600 watters which by the way wont even do microwave popcorn (7 min for popcorn) will consume way more than that little inverter can handle. I have a Xantrex 1000 which is a 2000 watt surge, and it can run a 1000 watt microwave, but at that heat, it would run a group 27 battery totally dead in 28 minutes from fully charged.
And that's totally dead - not to the 50% max you're supposed to do.
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