Sub Freezing temps and motor startup

[KVX10]

I've recently experienced electric motor startup problems like high thermal temps. for motors 150hp and larger that drive well pumps. I've never had to look into the realm of sub-freezing temps creating a larger current draw on startups as I live in a milder region of the country. I would think there is a relationship between the colder temps and the work level of a motor to start. The voltage from the source is within range. Can someone shed some more light on this subject?
Thanks.

 

[Marke]

Is it a higher start current, or a longer start time. I suspect the latter due to mechanical issues.

Best regards,
Mark.

Mark Empson
L M Photonics Ltd

 

[ankervik]

Are you using Arctic duty motors? Perhaps you should be if you are operating in severe winter conditions with prolonged sub-zero temperatures. There are several operational factors to consider. Arctic duty motors are designed for ambient temperatures as low as -70F. They have different bearing tolerances than standard motors & use grease with a synthetic based lubricant. Often the rotor shaft is made of a higher grade steel & the windings are fitted with space heaters.
If you don't have Arctic duty perhaps you could fit space heaters into your existing motors & see if that helps any?

 

[dpc]

These are submersible well pump motors, vertical turbine pumps, or what?

 

[Compositepro]

Are you sure its not just simply that the water in the pumps is frozen(fully or partially with ice chunks)?

 

[jraef]

I think you need to define "high thermal temps" a little better for us, as well as how you are determining this on a submersible pump (if it is indeed submersible). I have worked on cryogenically cooled submersible LNG pump systems (-200C), the starting issues were not significantly different than normal.


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[MotorVib]

Grease is the major problem that you will have at cool temps. By the way how cools is it?

Chris

"In this house, we obey the laws of thermodynamics." Homer Simpson