Another 220 Volt Compressor Question...

[Junkman]

I am getting around to finishing the wiring in my new garage (the old one is full) and I want to install my 5 HP compressor in there. I have found the motor specs here on this web page. Now my question is, what is the correct size circuit breaker for this application? I would also like to wire this with a twist lock plug since the compressor is skid mounted with wheels.. (makes for easy cleaning of floor). I would like to know the correct NEMA twist lock plug to use for this application. It is presently wired with 12 gauge wire, however, I am not certain if it should be 10 or 12 gauge. Is 12 gauge adequate? Thanks for the help..

 

[Mark_in_NH]

I do not knw what plug should be used.
But at 23 full load amps, I would put it on a 30 amp double pole breaker and you should replace your 12 guage wire with #10. 12 guage is only rated for 20 amps while 10 guage is rated for 30 amps.
Having a Master Electrition for a Dad has come in real handy alot of times. /forums/images/graemlins/grin.gif

 

[TWINKLE_TOES]

For the twist lock 220 V, 30Amp

Look Here

"L" equates to locking and the L6-30 is a good choice.

Is this a test?? /forums/images/graemlins/smile.gif

 

[Inspector507]

L6-30R for the receptacle and L6-30P for the attachment plug.
#0 Amp circuit......#10 wire

Hope this helps. Hope I passed the test as well /forums/images/graemlins/smile.gif

 

[TWINKLE_TOES]

<font color="blue"> Hope I passed the test as well </font>

507, The teacher doesn't have to take the test, but you can grade your own answer. /forums/images/graemlins/grin.gif

 

[R_squared]

You might want to consider 8 gauge conductor and a 40 amp breaker. Continuous run amperage on a true 5 Hp motor is approximately 23.5 amps. The cost of 8 gauge wire is not much more than 10 gauge wire. If a 30 amp breaker trips on continuous run, then you could swap it with a 40 amp breaker and have the proper gauge conductor in place. You will have more plug choices also.

 

[rambler]

Still don't see how they can rate air compressors & is it shop vacs for 5 hp, and sell with a 110 regular plug. They rate those motors to theoretical max, which is not actually the hp rating as we normally understand it.

--->Paul

 

[johnbilt]

Hi

I am using #10 on a dual 30A breaker per code. It works fine for my large compressor with a 7 HP motor. I looked at the spec for the motor that you listed. 89 Lbs !! WoW I don't believe mine is that heavy, but I've never removed it from the tank.

I don't think you will see much benefit from using #8 wire, unless you are making a long run of 100ft or so. You should use a 40A breaker sized properly for the supply wire if you should use #8. I think most people jump to a 50A, #6 circuit at this point. I suspect the terminals in the compressor relay are not sized for this large wire.

Good Luck

John /forums/images/graemlins/cool.gif