otrfun wrote:
Most microwaves are rated at 1,100-1,500 watts with a bit of inrush during startup. Even our Champion 3100 inverter generator tends to struggle a little starting up larger 1,500 watt units. The OP might find it cheaper and less hassle to simply replace their current microwave with a smaller 700-900 watt unit vs. purchasing another generator. Even the most crippled 2000 watt generator should be able to easily power a 700 watt microwave.
Another possibility is to replace the microwave with an inverter microwave such as the Panasonic Microwave Oven NN-SD372S. This is a 950 watt microwave that can be set at 10 different wattages. The lowest setting is under 600 watts. Of course it will take longer to cook, but has the advantage that you can use it at full power when you have hookups, and reduced power when running on an inverter or small generator.
It also does a better job of defrosting than a standard microwave. You don't get cooked outer edges of meat, since it used lower power to defrost.