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Electric Motors/Electric motor overheating


I have a centrifugal cage blower motor assembly from a home heating unit that I use in my shop to blow air around.  It has a GE 5KCP36FG motor in it.  It starts right up, works good but after about 15 mins, it shuts down due to excessive heat.  What would be the cause of this?  I can't seem to find anything wrong.  The cap checks good.  Does this motor have an internal cap winding switch?  Baffled!


When the motor was in a furnace assembly, the circulating air actually keeps the motor cool with the return air going over the motor.
This is within a closed system.

When the blower is sitting in the open, the motor does not get the same cooling it requires, thus getting hot and tripping on the thermal switch, which is embedded in the winding.
Either reroute some air over the motor, or measure the temp of the motor. It shouldnt be more than 40 deg C over ambient.
If its within this range then you can by pass the thermal overload by opening up the motor and joing the wires together. instead of via the thermal contacts.

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Harcharan Singh Diocee


Electric motor winding redesign, AC and DC. Troubleshooting, motors controls generators. Vibration analysis, dynamic balancing, root cause analysis: electrical and mechanical.


thirty five years electro-mechanical and Senior Management


Journeyman Motor Rewinder, Millwright, Industrial Electrician, Vibration Analyst level II. Certified Electrical Technician ASTTBC, FSR Class B, in BC. Laser alignment specialist. Marine machinery repairs. Business Management Certificate. Last 19 yrs as Plant Manager

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