6wheeler 669 #1 Posted April 17, 2014 I have a question for the electrical Guru's. I have an Ingersoll Rand Air compressor that was my dads. It has an AJAX 5hp. 230v motor on it. It is a very large compressor with an 70 gallon tank. It stands about 6and a half feet tall. As I said, very large. The wiring that already comes from the panel looks like 12/3 outdoor standard wire. I don't think this is near heavy enough wire. Also it is on a 30 amp breaker. When I hooked it up, The motor starts fine and slows down after about 30 seconds of running and takes off again. It does this cycle about a half a dozen times and then blows the breaker. Then it smokes a bit out of the motor. The oil capacitors don't even get warm. But, the 4 capacitors inside the back ( rear) of the motor( I can't remember the correct name for those) are very warm to the touch. Could the wire be to light and creating too much resistance? The feed wire is app. 30 feet long. I was thinking the motor might not be getting enough power for a motor that size. I just had the motor gone through and all of the windings and starter are fine plus they put in all new capacitors. I am stumped. HELP. Share this post Link to post Share on other sites
953 nut 59,748 #2 Posted April 17, 2014 (edited) Do you know what wire size and amp breaker your dad used? 12-3 is rated for 20 amps. If it draws more than 20 amps then even at 30 feet you will have a lot of voltage drop on # 12 wire. If the motor has an information plate on it you will find a running amps listed, if it is not higher than 16 amps (20 amps X 80%) then your wire size is OK, but the breaker should be changed to a 20 amp to properly protect the wire. Make sure all connections are tight. Hope this helps. Edited April 17, 2014 by 953 nut Share this post Link to post Share on other sites
HorseFixer 2,013 #3 Posted April 17, 2014 What does the amperage rating say on the Motor? I would guess 5 Horse at 30+ amps which would mean 10ga to 8 ga Wire. The Smoke out the motor don't sound good to me. ~Duke Share this post Link to post Share on other sites
HorseFixer 2,013 #4 Posted April 17, 2014 Beat me to the draw 953 Personally I wouldn't have fired it up until wiring was checked, Now I fear windings are smoked from possible brown out! ~Duke Share this post Link to post Share on other sites
6wheeler 669 #5 Posted April 17, 2014 (edited) 5hp. 1725 rpm. cyc.60 22amps code G. If I start it again? It runs like nothing happenedand doesn't smoke until it does the cycle again. NOT starting it again til I figure this thing out. BTW ran fine when it was not under load. Edited April 17, 2014 by 6wheeler Share this post Link to post Share on other sites
squonk 43,722 #6 Posted April 17, 2014 Wire certainly not big enough to begin with.. Also did this compressor come with a magnetic starter or was there one where it was located before? Share this post Link to post Share on other sites
KC9KAS 4,744 #7 Posted April 17, 2014 If it ran fine at your fathers home and your breaker is the same size as his, something else is causing the problem. Maybe the start/run capacitor, or an unloader valve on the compresser for easier starting may be the problem. Share this post Link to post Share on other sites
bitten 134 #8 Posted April 17, 2014 Might sound like a dumb question but what is the voltage coming into the compressor? Share this post Link to post Share on other sites
