IR 5HP pops breaker after 5 secs of running

by Carl


I have a 2 stage IR with 80 gal tank and 220vac 5 hp motor. After about 4-5 seconds it blows the breaker.

The model I have is:

I checked both caps and the run cap was bulged and ohmed as open. So I replaced both caps with same model and specs. It still blows the breaker after 5 seconds! Ugh!

Any help would be great.

Comments for IR 5HP pops breaker after 5 secs of running

Click here to add your own comments

Oct 12, 2018
by: Doug in

The only way that makes sense, if it's not blowing the control line or motor breaker/fuse(s), is if L1 is grounded somewhere before it/them.

Ugh, indeed.

Good luck, and keep on keeping us posted...

Oct 12, 2018
Well just checked the amp draw...
by: Carl

Ok, just checked the amp draw by hooking my amp clamp to the breaker panel and flipping the breaker to check amp draw. It’s pulling on one leg 120 on startup then after it runs for a sec or so it drops to around 75 amps.

I went to check the other leg and now there’s nothing. No motor starting up. Breaker is locking on and off but there’s nothing happening so now I need to check to see if I’ve burned wiring or contacts in the pressure switch by pulling so many amps.

I tend to over design stuff so I used 6 ga wire, so more than likely it the contacts in the pressure switch or the motor is completely burned up now. Idk? Ugh!

Oct 12, 2018
Info so far
by: Carl

Thanks for the ideas. From the way it was acting and having the run cap test open, I actually thought it was going to fire up and run like normal when replacing the caps...but it didn’t.

The motor and pump sound good as if everything is fine but then the breaker pops after 5 secs. Oil level is good, however I should change it soon. This is cold starting with no air or close to no air in the tank when this happens. I can check amp draw and check it with a larger breaker. I don’t have a meter with capacitor setting. I can only check for open with ohms and both the new ones showed a reading so they are not open.

Oct 06, 2018
IR 5HP blows breaker
by: Doug in

Ordinarily, that kind of draw would have a 50-60 amp breaker, so it could be it's getting weak.

But we still to know what it does during the 5 seconds before the breaker blows.

Oct 05, 2018
by: Carl

Also the motor has a 22.7 amp rating so I have a 30 amp breaker on it that’s been working fine for about 2 years. And the capacitors are: 270-324uF (start), and 50uF (run).

Please help!!

Oct 04, 2018
blows breaker
by: Doug in

Please tell us what it does during the 5 seconds before the breaker blows.

You might recheck those new caps, too.

Click here to add your own comments

Add your own question or comment. It's easy to do. How? Simply click here to return to Ask A Compressor Question.