THANKS,
yes, overload realy was there.Both power circuit and control circuits.
Electro mechanical ol realy.
i dont check phase lose but i found phase to phase power 385-387-389
Regards.
biti
I'm not trying to be picky, just correct, because I'm suspecting Ingersol Rand of a possible marketing trick, hype or miss direction.
Is it possible that you mean voltage? or do you mean amps measured on the line?
it is an ingersoll rand compressor motor and running with load maximum time.
Again, not trying to be picky just trying to get to the root cause of the problem. Are you saying " It's an Ingersol Rand compressor motor and
it's running at maximum load all of the time?
power is hp 200,hz 60,voltage 380,star delta control.
I'm not sure it's part of the problem, but the 60 hz thing bothers me. I thought 50 hz was standard with that voltage.
motor rated current 288 and main contactor after use ol realy and current setting is 180 amps.
I think BryanG has it correct and Ingersol Rand is guilty of running the compressor in the service factor zone
You say that it is Star/Delta started, so I am assuming that the overload is seeing Phase current rather than Line. In which case the overload should be set at 0.58 * Line current, or 167 Amps. Another way of doing the same calculation is Line current divided by 1.732, 1.732 being the square root of 3.
yes, it is installed very hot place and the outside temperature is always 30 to 40-degree centigrade. Motor all side close by the cover.
There was no mechanical or bearing problem. motor found very free.
I cannot see where you indicated exactly what type of overloads. Are they eutectic alloy, bimetal or electronic?
If I'm right that you are running at maximum load most of the time and Ingersol Rand has loaded the motor in the service factor area, then placing eutectic alloy or bimetal overloads in the same temperature as the motor would be one step closer to protecting the motor.
If they are electronic it won't make any difference.
yes,compressor installed after with in oneyear motor fail and we make it rewinding.it was 3 years before and now again fail.motor grounded,short circiits coil to coil.
Not sure how Ingersol Rand is loading your compressors, but where I work we have 6 Ingersol Rand Centac compressors 700 hp each (yes I know it's an insane amount of air). The Centac's use a 4 to 20 current input from a motor current tranducer to limit the motor loading. If you have the same then you can limit the motor loading to give you more motor life.