Anyone familiar with large air compressors popping breakers?

W

Will Albers

New member
Nov 6, 2017
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This is only quasi GMC related, but while working on the coach, i noticed my impact gun was slowing down. I have a 240v Ingersoll TS4 compressor that
popped the breaker. I reset and found that its drawing 75amps at startup, sounds and smells a little funny while running, before it pops the breaker
about 10 seconds in.

It does build pressure while it runs

I'm hoping start or run capacitor. I figured I'd replace both to be sure, but I'm super hesitant as its a 240v motor.

So, any advice on what to look for before i decide to replace the caps? Now does one discharge a 240v cap?
--
1978 Palm Beach.
Detroit Michigan
In need of several pieces to replace water damage
 
Before touching the terminals of an electrolytic capacitor I would short it out with a screwdriver to be sure it was discharged.
--
Roy Keen
Minden,NV
76 X Glenbrook
 
You could check the voltage on the caps... I think you will find it to be
zero because it is working in an AC circuit rather than a DC.

High current is an indication of a heavy load which could come from a
shorted cap or motor load. Motor load could be from shorted windings or a
friction load from bad bearings or other parts not moving as freely as they
should.

Caps are a good place to start... They are the cheapest and easiest parts.
Is this a belt drive system? If so try taking the belt off and rotating the
motor and compressor feeling for drag. There should be little drag other
the compressing air. If you are working with an empty tank that should be
minimal. Basically, you are looking for bad bearings or cylinder friction.

Does the motor run well without the compressor? There should be almost not
true power used.

If the motor and the compressor check out, make sure you are not over
pressured.

> Before touching the terminals of an electrolytic capacitor I would short
> it out with a screwdriver to be sure it was discharged.
> --
> Roy Keen
> Minden,NV
> 76 X Glenbrook
>
> _______________________________________________
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--

*John Phillips*
 
Easy stuff first. Barring a short, high current indicates a locked armature. On a compressor, this is often due to residual pressure. Are you sure
the compressor relief valve is opening? If it doesn't, it causes the compressor to start under load, and many haven't the power.

--johnny
--
76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"I forgive them all, save those who hurt the dogs. They must answer to me in hell" - ol Andy, paraphrased
 
> This is only quasi GMC related, but while working on the coach, i noticed my impact gun was slowing down. I have a 240v Ingersoll TS4 compressor
> that popped the breaker. I reset and found that its drawing 75amps at startup, sounds and smells a little funny while running, before it pops the
> breaker about 10 seconds in.
>
> It does build pressure while it runs
>
> I'm hoping start or run capacitor. I figured I'd replace both to be sure, but I'm super hesitant as its a 240v motor.
>
> So, any advice on what to look for before i decide to replace the caps? Now does one discharge a 240v cap?

Will,

Popping the breaker after 10 seconds means it is most likely the run capacitor that is bad. This will make for high current both starting and
running. As it is a 5hp motor, it will most likely have both a start and a run capacitor. The larger is usually the starting cap, but I the time I
had a lot to do with them, if you replaced one, you would get to replace the other in a week.

Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan
OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
 
Johnny - I want to say yes, pressure is down to 20 psi, and it releases a
burst of pressure every time it shuts off, telling me its clearing the
relief valve. I could be wrong - any way to check?

Matt - I was thinking the same - They are $15 each, so i planned to replace
both. 2 screws each. VERY accessible.

Thanks all. I'll start with the caps and see how it goes.

> > This is only quasi GMC related, but while working on the coach, i
> noticed my impact gun was slowing down. I have a 240v Ingersoll TS4
> compressor
> > that popped the breaker. I reset and found that its drawing 75amps at
> startup, sounds and smells a little funny while running, before it pops the
> > breaker about 10 seconds in.
> >
> > It does build pressure while it runs
> >
> > I'm hoping start or run capacitor. I figured I'd replace both to be
> sure, but I'm super hesitant as its a 240v motor.
> >
> > So, any advice on what to look for before i decide to replace the caps?
> Now does one discharge a 240v cap?
>
> Will,
>
> Popping the breaker after 10 seconds means it is most likely the run
> capacitor that is bad. This will make for high current both starting and
> running. As it is a 5hp motor, it will most likely have both a start and
> a run capacitor. The larger is usually the starting cap, but I the time I
> had a lot to do with them, if you replaced one, you would get to replace
> the other in a week.
>
> Matt
> --
> Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
> Electronically Controlled Quiet Engine Cooling Fan
> OE Rear Drum Brakes with Applied Control Arms
> SE Michigan - Twixt A2 and Detroit
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
I'll second both the caps and the unloader valve. It's likely one or the other.
Most larger compressors will not start loaded, the unloader malfunctioning will cause the breaker to blow.

Is is audibly struggling? Sounds like it having to try too hard?
--
Justin Brady
http://www.thegmcrv.com/
1976 Palm Beach 455
 
No, it has a different sound, but not a struggling sound. It builds
pressure fine for the 5 or so seconds, until the amperage draw flips the
breaker. It releases a blast of air from the unloader each shut down, as it
normally does.

> I'll second both the caps and the unloader valve. It's likely one or the
> other.
> Most larger compressors will not start loaded, the unloader malfunctioning
> will cause the breaker to blow.
>
> Is is audibly struggling? Sounds like it having to try too hard?
> --
> Justin Brady
> http://www.thegmcrv.com/
> 1976 Palm Beach 455
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Since it runs for 10seconds before tripping the breaker, it could also be a blocked or restricted check valve.

If this is the case, the unloader allows the system to start with no load, but as pressure builds, the check valve restricts airflow, effectively over pressuring the compressor and tripping the breaker.

If your caps don’t solve the problem, I would try disconnecting the line from the compressor to tank and test run it. While you are there, also verify that the check valve is clear and functional. The check valve is typically between the compressor line and tank, and the unloader line connects to it.

I’ve seen two check valves that failed and effectively preventing the valve from fully opening, causing a major restriction to airflow. This overloads the compressor and motor, tripping the breaker.

Les Burt
Montreal
'75 Eleganza 26'

>
> No, it has a different sound, but not a struggling sound. It builds
> pressure fine for the 5 or so seconds, until the amperage draw flips the
> breaker. It releases a blast of air from the unloader each shut down, as it
> normally does.
>

>>
>> I'll second both the caps and the unloader valve. It's likely one or the
>> other.
>> Most larger compressors will not start loaded, the unloader malfunctioning
>> will cause the breaker to blow.
>>
>> Is is audibly struggling? Sounds like it having to try too hard?
>> --
>> Justin Brady
>> http://www.thegmcrv.com/
>> 1976 Palm Beach 455
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
> _______________________________________________
> GMCnet mailing list
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> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
OK, sounds like the easy fix is covered and it's unloading properly. Options are a bad capacitor, badcap switch if it has one, dry bearings, shorted
turns. This is a complete integrated uni? as opposed to a separate motor and compressor with a belt?

--johnny
--
76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"I forgive them all, save those who hurt the dogs. They must answer to me in hell" - ol Andy, paraphrased
 
two separate units, belt driven. Caps are ordered. I'll report back once i
swap em over

On Mon, Apr 30, 2018 at 9:31 AM, Johnny Bridges via Gmclist <

> OK, sounds like the easy fix is covered and it's unloading properly.
> Options are a bad capacitor, badcap switch if it has one, dry bearings,
> shorted
> turns. This is a complete integrated uni? as opposed to a separate motor
> and compressor with a belt?
>
>
> --johnny
> --
> 76 26' Eleganza(?) with beaucoup mods and add - ons.
> Braselton, Ga.
> "I forgive them all, save those who hurt the dogs. They must answer to me
> in hell" - ol Andy, paraphrased
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
So it wasn't the caps. No change. The motor starts to smoke when ran
without the belt.

Can 5 HP motors be repaired or do you just replace?

> two separate units, belt driven. Caps are ordered. I'll report back once i
> swap em over
>
> On Mon, Apr 30, 2018 at 9:31 AM, Johnny Bridges via Gmclist <

>
>> OK, sounds like the easy fix is covered and it's unloading properly.
>> Options are a bad capacitor, badcap switch if it has one, dry bearings,
>> shorted
>> turns. This is a complete integrated uni? as opposed to a separate
>> motor and compressor with a belt?
>>
>>
>> --johnny
>> --
>> 76 26' Eleganza(?) with beaucoup mods and add - ons.
>> Braselton, Ga.
>> "I forgive them all, save those who hurt the dogs. They must answer to
>> me in hell" - ol Andy, paraphrased
>>
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
>
>
 
Sometimes it’s cheaper to replace than to rewind. All depends on the frame type and availablility. You can probably find a reasonably priced replacement from an internet vendor.

Les Burt
Montreal
'75 Eleganza 26'

>
> So it wasn't the caps. No change. The motor starts to smoke when ran
> without the belt.
>
> Can 5 HP motors be repaired or do you just replace?
>

>>
>> two separate units, belt driven. Caps are ordered. I'll report back once i
>> swap em over
>>
>> On Mon, Apr 30, 2018 at 9:31 AM, Johnny Bridges via Gmclist <

>>
>>> OK, sounds like the easy fix is covered and it's unloading properly.
>>> Options are a bad capacitor, badcap switch if it has one, dry bearings,
>>> shorted
>>> turns. This is a complete integrated uni? as opposed to a separate
>>> motor and compressor with a belt?
>>>
>>>
>>> --johnny
>>> --
>>> 76 26' Eleganza(?) with beaucoup mods and add - ons.
>>> Braselton, Ga.
>>> "I forgive them all, save those who hurt the dogs. They must answer to
>>> me in hell" - ol Andy, paraphrased
>>>
>>>
>>> _______________________________________________
>>> GMCnet mailing list
>>> Unsubscribe or Change List Options:
>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>>
>>
>>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
I'd just replace. Check your local CL, there's a guy here locally that buys damaged compressors and parts them out.
I've also replaced true industrial 5hp motors with leeson single phase motors with good results.
--
Justin Brady
http://www.thegmcrv.com/
1976 Palm Beach 455
 
I have a 80 gallon, 5 horsepower, belt driven, 2 cylinder, Ingersoll Rand
compressor. It is at least 30 years old. I have had the motor repaired once
a few years ago. There is a local electric motor repair shop here in Salem,
and I had him repair my motor. Base cost was $100.00 plus parts. It needed
both the start and run capacitors. Still cheaper than a new motor. Runs
fine now.
Jim Hupy
Salem, Or
78 GMC ROYALE 403

> I'd just replace. Check your local CL, there's a guy here locally that
> buys damaged compressors and parts them out.
> I've also replaced true industrial 5hp motors with leeson single phase
> motors with good results.
> --
> Justin Brady
> http://www.thegmcrv.com/
> 1976 Palm Beach 455
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
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