Gauge for 100 ft. extension cord

[Andy]

I have an air compressor that uses 13.5 amps.

What gauge would I need for a 100 ft. extension cord ?

Thanks, Andy

[hubops]

... depends on the voltage. John T.

[mike]

[Stormin' Norman]

If the compressor operates on 110-120 volts AC. you could get away with a 12 ga. x 100ft. extension cord. However, if it were me, I would bite the bullet and get a 10 ga. cord, that way I would not be concerned about the initial starting current draw of the motor AND I would have a little excess capacity just in case I want to use a second and third tool at the work site. For example, if you are spray painting, you might want to use a 1/2 hp drill to mix a 5 gallon bucket of paint while the compressor is running.

[clare]

Nothing smaller than a 12, for sure.

[Ralph Mowery]

The voltage does not matter. It is all the current and distance.

[Ralph Mowery]

You need atleast 10 gauge. Even at that, there is one more thing to look into. How far from the main breaker box to where you are going to plug the cord into ?

The air compressor is probably going to need more than the 13 amps to start up. That may or may not be a problem.

[hrhofmann]

The reply from "Hub" that the voltage did not matter is wrong. If you had a supply voltage of 24 Volts, and a 10 Volt drop in the power cord, that wo uld be pretty much a loser. The same 10 Volt drop at 120 Volts would not b e an issue under reasonable circumstances.

[Ralph Mowery]

You do not size it for a number of volts drop, you size it for a percentage of the stating voltage drop. That is why you only need to know the amps and distance.

[mike]

A percentage of a voltage that you don't care to know? Maybe I just don't know how to determine the stating voltage?

[trader_4]

d a supply voltage of 24 Volts, and a 10 Volt drop in the power cord, that would be pretty much a loser. The same 10 Volt drop at 120 Volts would not be an issue under reasonable circumstances.

Agree, the effect you describe is correct. From a practical standpoint, he' s likely talking about 120v and I'd go with 10g. I've seen plenty of motor s struggle, overheat, trip breakers on smaller cords, while they run fine o n a heavy one.

[Terry Coombs]

A hundred feet of air hose is probably cheaper than a heavy gauge cord that long ... just sayin' . Put a portable receiver tank on a tee near where you're working to help with surge usage .

--

Snag

[clare]

But 1 5% drop on a 24 volt line would require a much heavier cord than a 5% drop on a 240 volt line. - so yes, voltage matters a bit. However, the aitr compressor is going to be either 120 or 240, so the difference is significantly smaller.

[Checkmate, DoW #1]

ITYM 10 gauge, Kernel.