Need help wiring my compressor

[trifiveshawn]

I am wiring up my air compressor in my barn. It says 230volts and 17.3 amps on the motor. The local electrical supply told me 12/2 would be ok and sold me it an outlet and a breaker ( breaker says 10ka 120/240v) Compressor worked great at my old shop this morning, hauled it home and wired my electric up. Went to try it out the motor hums and barely trys to turn over. Could the breaker not be strong enough or my 12/2 not enough? The compressor is less than 6 ft from the box if that helps. Help please lol

 

[wyliesdiesels]

Do u have pics of the breaker panel and compressor wiring? Could be a number of things! Is the breaker double pole? Do u have a multimeter to test the voltage at the motor terminals or starter?

 

[trifiveshawn]

compressor has a plug in wired from factory, I just wired outlet in, all my meters are at work.

 

[98ssuck]

The 10kA is the interrupting capacity of the breaker. Is the 17.3 amps the running or starting amperage? If 17.3 is your running amperage your breaker is a little small because breakers are only rated for %80 of their stamped marking. But if it doesn't trip you should be fine. As for your compressor issue it sounds like you have a low incoming voltage. Check your voltage at the plug. If it is low check the incoming voltage at your pannel. There is also the unlikely possibility that there is something wrong with the compressor motor and the is it is just a conquincidence that the issue arises after using a different receptacle.

 

[KenC]

My guess, with the info available, is that the feed to the barn may be undersized causing voltage drop before it gets to the breaker in the barn.

Only way to tell is measure the voltage, under load.

 

[trifiveshawn]

heres the motor info

 

[pattenp]

If the compressor came factory wired with a cord and 20A plug then a 20A 240V circuit should be fine. I assume the plug looks like this......

 

[trifiveshawn]

yes that's the one.. barn had compressor in it and welders from previous owner

 

[LG63]

Did you lay the compressor down to move it? Can you turn the pump by hand?

 

[trifiveshawn]

nope left upright, yes pump will turn by hand

 

[wyliesdiesels]

Is it possible that you might have reversed one of the hots and ground in the outlet, so the motor is only gettin' 120v instead of 240v? Too bad u dont have a meter handy. Checking supply voltage is always the first thing i do when troubleshooting! Theres really no other troubleshooting to do until supply voltage is checked.

Looks like your breaker is a double pole/240v. What is the number on the breaker handle? And no, theres no such thing as a breaker not being sized strong enough that would prevent a motor from running. A breaker functions kind of like a switch, opening itself when theres too much current/amps flowing through it! There could be the remote possibility that theres something wrong with the breaker and its causing voltage drop but this is very rare!

I assume u know how to wire this correctly but since u used 12/2, i have to ask- did u connect the black and white wires to the lugs/poles on the breaker? The white wire should NOT be connected to the neutral bar and should be taped black(or red) at both ends!

 

[trifiveshawn]

Got it.. new breaker was bad.. just my luck buy all new stuff and its bad lol

 

[wyliesdiesels]

Definitely wierd the breaker was bad right from the getgo!