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LightningHeart 04-30-2008 10:25 AM

Double Amperage?
 
I've got a 3000 watt power inverter with 4 15 amp outlets. I need 20 amps to run a electric log splitter. Can I wire two outlets in parallel and get 30 amps?
I don't want to fry the inverter by trying out without knowing.

Thanks

LawnGuyLandSparky 04-30-2008 10:32 AM

3000 watt peak or 3000 watt sustained load? a 20 amp load is 2400 watts so, you should be able to get your 20 amps from any one of the 4 receptacles. The inverter supplies 3000 watts to the 4 receptacles total, not 750 watts to each one individually...

LightningHeart 04-30-2008 12:24 PM

The Inverter is 3000w with a 6000w surge capacity. My previous inverter was 1500/3000 with 2 110v outlets. It blew 4 30 amp fuses when I tried to start the electric splitter ( I'm trying to bring the splitter to the wood rather than vice versa). I have a solar panel setup and 4 deep cycle batteries mounted in my pickup to supply portable power.
The new inverter has 4 outlets which I thought gave me 750 watts at each outlet (3000/4) but it says 1500 at each outlet on it. I assume they mean 1500 surge. I read that amps=watts divided by volts so that would give me 1500/110 or 13.64 amps at startup?. So the 20 amp draw from the splitter starting would be too much , no?

micromind 04-30-2008 06:50 PM

The starting current of a typical AC motor is roughly 6 times the running current. If the running current of this motor actually is 20 amps (that'd be around 2HP), then the starting current would be about 120 amps. If the source can't come up with enough current, the voltage will dip down a bit, if it's not too much, the motor will start, but slower than usual.

I might be surprised, but I doubt that a 3000 watt inverter will start a 2HP motor, even unloaded. 6000 watt surge is only 50 amps at 120 volts. The inverter might see the motor as a short circuit, and trip out. Worse yet, the output of most inverters is a 'modified sine wave'. It's sort of a stair-step, rather than a smooth slope. Motors don't like distorted waveforms, so both starting and running torque will be lower. It'll also cause the motor to run hotter.

As far as the outlet rating goes, the 1500 watts is more a function of pin configuration (15 amp) than anything else. In fact, it's completely legal (codewise) to put 15 amp outlets on a 20 amp circuit, and is actually a common practice.

Rob

sevver 04-30-2008 07:28 PM

Coleman makes a nice little generator that you can carry around that I bet would run it. We used to run everything with ours, core machines, multiple 3" pumps, water main tapping machines, you name it. Plus it was around $300.


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