I have a 6.5 hp compressor(120V), that will only run about 1.5 min. before tripping the 15A breaker. Should I be using a larger amp breaker, or is something wrong in the wires(too small?)

Are you using an extension cord, and if so - how long of one? Is there ANYTHING else being powered off of that same breaker at the same time?

No ext. and a 60 watt bulb...

Well.... a 6.5 hp 120 V motor pulls around 40 amps (at 6.5 horse) I'd say you need a bigger breaker.

Of course it does really make 6.5 hp all the time, but I'd still say your on the small side. My 5 horse is plugged into a 20 amp circuit, and it hasn't tripped yet, but I don't run nothin' else on that circuit while it's running.

Chad

There should be a plate affixed to the side of the motor that has the specs on it. Volts, Amps, RPM, etc.... If, for example it says 12.5 A, then you would need to use a 15 Amp breaker. If it says, again for example, 19 A, then you would need a 20 Amp breaker. As DRM mentioned, if there is anything else on the circuit using power at the same time, that could trip it. It's best to use as short of a cord as possible and a dedicated circuit for the compressor. That way every bit of the rated power for the circuit is available to the compressor.

Yes you need a new breaker 20a
but check the wires in the wall to make sure they'll handle 20a
unless you want a bbq house...

Or if your dryer is in your garage, just take the neg and one of the single positive legs and you now have 120 @ 30amp;)

Thats what i do, for the lil mig and air compressor, all 240 is two hot 120 lines and a nutral

Do not just throw in a bigger breaker! The breaker is sized to protect the wiring (ie keep you from burning down your house). A 6.5 HP motor should not be ran off any normal household (120V) circuit, the wiring is too small!

Check to see if you can change the motor over to 220V. Often you can move some wires in the motor and change the plug. That would get you down to about 20A load, and would be compatable with a household dryer or A/C 220V circuit.

If you have to run it on 120V, you need to run a special circuit, of proper gauge wire ($BIG$) from the breaker box...

So what gauge wiring do I need for a 40A breaker/max load?

HINT HINT read the motor label..................

Originally posted by Gozuki
So what gauge wiring do I need for a 40A breaker/max load?

It depend on the length of run, but you are looking at #8 GA min for a short 40A run! Most hosehold wiring will be 14GA, with some 12GA for large appliances, sometimes in the garage. But, 12GA is only reccomended for 20A. If you have a 15A breaker installed, it's probably 14GA wire...

You should also consider that a normal 120V plug is not rated to handle 40A. The plug could become a fire hazard. Check your hardware store for a high cap plug. They usually have the current rating on the box. You may have to use a 220V plug to get the 40A cap.

If you are going to go thru the effort to drop a new circuit, run a 40A or 50A 220 circuit. You can hook the compressor up to run on 1/2 the circuit (120V) for now, then you have a heavy plug that can handle a light welder or plasma cutter later...

Another problem that could be is a bad breaker. Like others have said, you do not want to randomly install a larger breaker, but you could try a new breaker if everything else checks out.