What size inverter do I need for my RV?
If you want to use a Microwave or multiple appliances at the same time, you'll need over 1,200 watts capacity. You'll also need at least 200AH (Amp Hours) of battery capacity (to run a microwave for brief periods). You'll need more battery reserve for longer periods and heavier loads. If you'll be cooking full dinners for 30 minutes, you'll need a 400AH battery capacity.
Just want to operate a TV or computer? Usually a 200 to 300 watt inverter is enough.
When it comes to buying an RV power inverter there are two ways to go:
One. Get a good, efficient 1,200W or larger inverter and feed the whole place. The best ones are 90+% efficient and no longer need to be matched to the load. They'll do nearly as well running a small load as a big one. Incredible but true.
Two. If you don't need a big inverter, consider having one or more smaller power inverters and use the size appropriate for the job at hand.
Maybe have an 800W for everything except a microwave. Perhaps a 300W for TVs, VCRs, stereos and satellite systems. A 200W palm-size may operate a small TV, small stereo, computer or breathing machine.