Looking for some help on why my Ingersoll Rand is tripping the overload on the motor. It's a 80 gal 5 hp 2 stage and was working perfectly at prior house. Moved and it sat for about 1 year. Have a 30 Amp double pole breaker with about 40 feet of WCU RX 10/3 w/ground (stranded wire) that goes to a Non-fused General Duty Safety Switch Discount brand new. Then about 8 feet of 10 AWG (solid core) wire. Not sure if it's the different wire type or something else. It goes up to 150 psi and then trips every time. Cold/hot days. I cleaned filter, pulley's turn by hand, the unit is very clean, blew out the switch with air and check values seem fine. Just not sure why it wasn't doing it at prior house. I have no electrical knowledge/abilities. I even had a electrician do the hook up in the breaker and disconnect box. Wires were previously ran into place. Where do I start? thanks in advance.
Electrical Wiring Issue?
- Thread starter tipseeker
- Start date
micromind
Well-known member
The first thing to do is measure the motor current while it's running and compare it to the nameplate.
If it's less then the O/L is bad. If it's more then look at the voltage as close to the motor as you can get.
If the voltage is good, and the current is high, check the run capacitor. If it has failed, the motor will still run but it'll draw excessive current.
If it's less then the O/L is bad. If it's more then look at the voltage as close to the motor as you can get.
If the voltage is good, and the current is high, check the run capacitor. If it has failed, the motor will still run but it'll draw excessive current.
walta
Well-known member
Just a wild guess but I think you are going to find that when the overload trips the voltage at the motor is lower than 240 Volts and at the last house it was higher.
The right way to diagnose the problem is to measure the voltage and current when it trips. Without numbers all we are doing is guessing.
For now, let’s assume the overload is working as it should and trying to prevent the motor from being damaged. Never reset the overload without waiting 15 minutes and allowing the motor to cool after it was overloaded.
30 Amps and a 10-gage wire is undersized for any real 5 horse motor. It is likely has a rating 28 Amps with a “service factor” of 15% that means the manufacture expects the motor will be pulling 32.2 for a short period. Ideally you would have a larger breaker and heavier wire and there would not be any plugs and receptacles on this circuit.
Walta
The right way to diagnose the problem is to measure the voltage and current when it trips. Without numbers all we are doing is guessing.
For now, let’s assume the overload is working as it should and trying to prevent the motor from being damaged. Never reset the overload without waiting 15 minutes and allowing the motor to cool after it was overloaded.
30 Amps and a 10-gage wire is undersized for any real 5 horse motor. It is likely has a rating 28 Amps with a “service factor” of 15% that means the manufacture expects the motor will be pulling 32.2 for a short period. Ideally you would have a larger breaker and heavier wire and there would not be any plugs and receptacles on this circuit.
Walta
Chuckster in NJ
Well-known member
FIRST! Need some running current and voltage readings……. 25%, 50%, 75%, 100% of compressor PSI.
justsam
Well-known member
Try backing off the high limit on the pressure switch to say 140 PSI. Does it still trip? Your call but 150 seems a little high to me, my 60 gal I/R is set to cut in at 85 psi and cutoff at 120 psi.
That will likely work, but it's a band-aid. My 30 gallon cuts off at 155psi no problem, factory setting.
Post #3 has all the relevant info/tests
wyliesdiesels
Well-known member
my dewalt 60gal with 3hp motor cuts off at 150psi no problem
Probably the difference in a single stage vs two stage compressors. Most 1 stg are set at 120 and most 2 stg are 175. At least IME.
It's not clear to me what is tripping, supply circuit breaker, motor starter overload or motor's internal protection? If it's the supply, I'd try another breaker. Could be a 30 that trips on the very lowest part of the range, another may not do that.
But, the real fix is a circuit with more capacity. Probably 8ga and 40a.
Of course all that is dependent on voltage being near 240.
justsam
Well-known member
OP said "Looking for some help on why my Ingersoll Rand is tripping the overload on the motor." Not clear to me why 10/3 was used as only 10/2 would be needed, but that is not the overload issue.
I'll bet you're wondering why it wasn't clear to me. So am I! read right over that.
In that case I'd suspect a defective overload. If it is the type internal to the motor, They do fail from time to time. Those are purely temperature sensitive devices. The bi-metal elements trip at the wrong time. again, assuming volts and current draw are ok, swapping that little thing may be all that's needed. Klixson probably has one that will work.
Thanks for all of the above responses. I was finally was able to borrow a Cen-Tech Clamp meter. I attached a pic of the name plan. Here's what I came up with.
Motor running current with meter at ACA 200 using clamp
1st test on White wire at motor See picture & also notice the black (burn) marks? not sure what that's about.
At start bounces up and levels at 24.7
at 40 PSI 25
at 80 PSI 25.7
at 120 PSI 26.4
Tripped thermal overload at 150 PSI at 27
1st test on Black wire at motor
at star bounces up and levels at 29.6
at 40 PSI 30.5
at 80 PSI 31.6
at 120 PSI 32.1 and tripped thermal overload
2nd test on White wire at motor
At start bounces up and levels at 25.6
at 40 PSI 26.1
at 80 PSI 27
at 120 PSI 27.8
Tripped thermal overload at 140 PSI at 28.2
2nd test on Black wire at motor
at star bounces up and levels at 30
at 40 PSI 30.6
at 80 PSI 31.5
at 155 PSI 32.9 and tripped thermal overload
3rd test is at the Non-Fused Safety Switch box
on Red wire
at star bounces up and levels at 29.8
at 40 PSI 30.6
at 80 PSI 31.7
at 120 PSI 31.8
tripped thermal overload at 125 PSI at 31.8
on Black wire
at star bounces up and levels at 28.8
at 40 PSI 29.3
at 80 PSI 30.4
at 120 PSI 31.3
tripped thermal overload at 135 PSI at 31.6
4th test was Volts at Press switch
241 with no motor running
239 at start
238 at 40 PSI
238 at 80 PSI
238 at 120 PSI
238 at 160 PSI when thermal tripped
then back to 241
5th test. Removed the compressor belt & just test at the motor again
the white wire was 30 amps at start and then stayed at 24.1 (this lead is from the Red wire in the safety box)
the black wire was 31 amps at start and then stayed at 28.4
Not sure if the above was what is needed to help determine my next steps. Thanks in advance
Motor running current with meter at ACA 200 using clamp
1st test on White wire at motor See picture & also notice the black (burn) marks? not sure what that's about.
At start bounces up and levels at 24.7
at 40 PSI 25
at 80 PSI 25.7
at 120 PSI 26.4
Tripped thermal overload at 150 PSI at 27
1st test on Black wire at motor
at star bounces up and levels at 29.6
at 40 PSI 30.5
at 80 PSI 31.6
at 120 PSI 32.1 and tripped thermal overload
2nd test on White wire at motor
At start bounces up and levels at 25.6
at 40 PSI 26.1
at 80 PSI 27
at 120 PSI 27.8
Tripped thermal overload at 140 PSI at 28.2
2nd test on Black wire at motor
at star bounces up and levels at 30
at 40 PSI 30.6
at 80 PSI 31.5
at 155 PSI 32.9 and tripped thermal overload
3rd test is at the Non-Fused Safety Switch box
on Red wire
at star bounces up and levels at 29.8
at 40 PSI 30.6
at 80 PSI 31.7
at 120 PSI 31.8
tripped thermal overload at 125 PSI at 31.8
on Black wire
at star bounces up and levels at 28.8
at 40 PSI 29.3
at 80 PSI 30.4
at 120 PSI 31.3
tripped thermal overload at 135 PSI at 31.6
4th test was Volts at Press switch
241 with no motor running
239 at start
238 at 40 PSI
238 at 80 PSI
238 at 120 PSI
238 at 160 PSI when thermal tripped
then back to 241
5th test. Removed the compressor belt & just test at the motor again
the white wire was 30 amps at start and then stayed at 24.1 (this lead is from the Red wire in the safety box)
the black wire was 31 amps at start and then stayed at 28.4
Not sure if the above was what is needed to help determine my next steps. Thanks in advance
Attachments
Cruzan80
Well-known member
So something is going on that your motor (which says it pulls 22.5 FLA) was getting above 30A when the belt was attached. You are starting close to the 30A limit when it turns on, and it shouldn't be. Honestly, the test without a belt is high as well, IMO.
Not looking good!! Motor FLA's are 22.5A and you're way above that. Readings on L1 should equal readings from L2.
Unloaded, the motor is still above FLA's.
Looks like the motor is failing. Seeing the black soot indicates wiring insulation is failing and shorting between winding turns or to ground.
Does this compressor have a solid ground connection back to the main panel?
Does this motor have 1 or 2 capacitors on it? Do you see or hear a centrifugal switch opening? Take a pic of the overall motor housing.
Look similar to this...more/less?......specifically the "humps"?
Unloaded, the motor is still above FLA's.
Looks like the motor is failing. Seeing the black soot indicates wiring insulation is failing and shorting between winding turns or to ground.
Does this compressor have a solid ground connection back to the main panel?
Does this motor have 1 or 2 capacitors on it? Do you see or hear a centrifugal switch opening? Take a pic of the overall motor housing.
Look similar to this...more/less?......specifically the "humps"?
Last edited:
This rant has the same "IR#" as your motor.
Not sure I agree with a few volts taking out the motor. The 60a cb vs. 30a cb won't cause any damage to the motor. A nuisance trip maybe, but that's it.
And another...........https://www.jalopyjournal.com/forum/threads/warning-ingersoll-rand-type-30-compressor-problems.431341/
another.....https://www.pirate4x4.com/threads/compressor-motor-help.954402/
Not trying to rain on the parade, but these guys blazed the same trail 15 yrs ago...........
Not sure I agree with a few volts taking out the motor. The 60a cb vs. 30a cb won't cause any damage to the motor. A nuisance trip maybe, but that's it.
And another...........https://www.jalopyjournal.com/forum/threads/warning-ingersoll-rand-type-30-compressor-problems.431341/
another.....https://www.pirate4x4.com/threads/compressor-motor-help.954402/
Not trying to rain on the parade, but these guys blazed the same trail 15 yrs ago...........
Last edited:
micromind
Well-known member
It's drawing more than full-load amps with no load......it's shot.
Here's a pic of the motor. It has two humps. I don't hear any switch when the motor is running with no belt. I do hear something switch when I turn off the motor. I makes a click as it's slowing down. Not sure what it is. Also the air pressure only releases when I turn off the compress when the overload trips. Went back and look at grounds. The ground in the pressure switch was a little loose. I tied it in with the ground from motor and rechecked without belt on. Slightly better #'s. However, I it tripped the overload with I put the belt back on.
Without belt, just motor
White at Start 29 then dropped and stayed at 23.7
Red at Start 24 for a second and then dropped to 22.8 slowly moved to 23.6
2nd test White at Start 29.2 for a second and dropped to 23.6
2nd test Red at start 29 for a second dropped to 26.4 to 26.2
with belt on
white wire at Start 57 for a second, then 24.2
at 40 PSI 24.9
at 80 PSI 25.6
at 120 PSI 26.4
tripped thermal overload at 135 PSI at 26.4
with belt on
Red wire at Start 34 for a second, then 30.4
at 40 PSI 30.9
at 80 PSI 32.1
at 120 PSI 33.1
tripped thermal overload at 135 PSI at 33.4
Motor is hot to touch, can only put hand on it for a minute or two.
Without belt, just motor
White at Start 29 then dropped and stayed at 23.7
Red at Start 24 for a second and then dropped to 22.8 slowly moved to 23.6
2nd test White at Start 29.2 for a second and dropped to 23.6
2nd test Red at start 29 for a second dropped to 26.4 to 26.2
with belt on
white wire at Start 57 for a second, then 24.2
at 40 PSI 24.9
at 80 PSI 25.6
at 120 PSI 26.4
tripped thermal overload at 135 PSI at 26.4
with belt on
Red wire at Start 34 for a second, then 30.4
at 40 PSI 30.9
at 80 PSI 32.1
at 120 PSI 33.1
tripped thermal overload at 135 PSI at 33.4
Motor is hot to touch, can only put hand on it for a minute or two.
Attachments
wyliesdiesels
Well-known member
What is the model of your clamp meter?
those start current #s are way low. in-rush current will be 4x-8x FLAs on nameplate.
Unless your clamp meter has circuitry capable of reading in-rush current, the readings will be wrong...
regardless, im guessing you have either a bad winding or a bad run cap
those start current #s are way low. in-rush current will be 4x-8x FLAs on nameplate.
Unless your clamp meter has circuitry capable of reading in-rush current, the readings will be wrong...
regardless, im guessing you have either a bad winding or a bad run cap
The click on shut down is the centrifugal switch. It's working correctly. It happens when you start it too but you don't hear it.
You can test the run capacitor under one of those humps. The run cap is the silver metal one.
You can test the run capacitor under one of those humps. The run cap is the silver metal one.