rockman7892
Electrical
- Apr 7, 2008
- 1,162
I have a 480V 200hp motor used on a screw pump application that I am looking to upgrade. This motor is currenlty being overloaded by the process and management wants to upgrade it.
This particular motor is constantly overloaded and as a result we keep tripping on overload. Production folks simply go and reset the overloads (against my reccomendation) and keep restarting the motor after trips. We have smoked this motor three times in the last month. We keep sending it out for repair put it back in service and the the same thing happens. Mechanics say that they have gone through all mechanical part of the application and there is nothing wrong, so it simply leds to the process loads.
We have taken several amp readings on the motor and see that it is pulling about 300A when the rated FLA is only 226A.
Management has asked me how we can get about 10% more capacity out of this motor. They have asked me weather we had to buy a larger motor (next standard size is 250hp) or if we could have this one rewound to a larger hp. Is it possible to have this motor rewound to give a larger hp maybe an additional 10% or so? Motor data is:
3-Phase
6 Poles
1190 rpm
60hz
FLA = 226A
S.F. =1.15
Alt S.F. = 1.0
Ambient = 40deg C
PF = 86.5
NEMA B
The one constraint we have is that if we upgrade to a 250hp motor then we will need to upgrade the starter size to a size 6 for the size 5 that we have is only rated up to 200hp. I'm assuming that this would be the same case even if we rewound the motor and upgraded the hp some?
I'm going to put a power logger on this motor. Other than power kW is there anything in particular I can look for as a red flag to say that there is a problem other than the process overload. Could power factor be a problem? Starting current?