Winding Temp
Winding Temp
(OP)
Hi Guys
We have a 250kw 1465 rpm 400v 3ph IP55 motor working on a pump application in an amb of 28 deg indoors. This motor has rtd's fitted and is giving a reading of 80 deg C. Can anyone tell me if this is ok at that temp and how can this be worked out.
The motors are rated class F
Thanks
We have a 250kw 1465 rpm 400v 3ph IP55 motor working on a pump application in an amb of 28 deg indoors. This motor has rtd's fitted and is giving a reading of 80 deg C. Can anyone tell me if this is ok at that temp and how can this be worked out.
The motors are rated class F
Thanks





RE: Winding Temp
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RE: Winding Temp
Class F can be taken a lot higher. From top of head, I think it is 155 C maximum (hot spot). But not recommended. Your bearings tend to lose grease if motor temperature gets too high. But windings can take it.
I would not start bothering before around 110 C - and that would be for bearings mostly.
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Winding Temp
I agree with the posts above.
Total temperature of 80 °C, at 28 °C ambient means 52 °C Temperature Rise, due to the losses generated under motor load.
Modern motors have around 80°C temperature rise over 40°C ambient for a total operating temperature of 120°C, with insulation class 130°C (B) or 155 °C (F).
Your motor is working very cool, may be the load is too low.
RE: Winding Temp
Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...