12v to 120v inverters

[vernj4]

Often have a need to use a jig saw, electric grinder or what ever.....so bought a 400 watt inverter for $20. Works well. Occasionally have a need to power an electrical device which draws more amps. The question is can I hook up a second inverter to the other battery and combine the outputs? This seems simple enough

[David Utz]

No. The inverters put out an alternating current, a sine wave or something to simulate a sine wave. To use two inverters together, you would have to synchronize the two waves to the exact same phase and frequency. If they are not exactly the same, they will short each other out. Honda makes a small gas generator that uses an inverter in place of the AC generator. They sell a synchronizer that will allow two of these to be put together (2000 watts + 2000 watts = 4000 watts total). So it is possible to sync two inverters if they designed for it and you buy the extra controller that matches the slave unit to the master. For your use, you just need to get a larger inverter or a small AC generator.

[DickWells]

Vern: Why not do what I did, and go to CostCo and get a 1000 W inverter for about $70 ? I got one a year or two ago. The maker wants you to put on a 150 amp circuit breaker or fuse at the positive 12V battery post. Breakers are costly. I got a 150A flat fuse from NAPA for 11 bucks and bolted it under the plastic battery cover to the output to the inverter. It runs clean enough to run our TV/DVD combo with a great picture, out in the Boonies. Should run any small power tool, since it's rated for up to 1200W for start-up and 1000 continuous.
Since CostCo seems to rotate stock a lot, you might find the same inverter at Sam's Club.
Good luck.
Dick Wells