Low RPM motor cooling

[jareese]

I did a quick search on this topic, saw some similar posts but not quite what I'm looking for.
I should have my lathe up and running in a couple more weeks, and I'm planning on practicing at LOW speeds. Is there a concern about heat generation with <500 rpm? In Low gear, my motor is squealing pretty good due to the lower frequency. I'm wondering if I need some additional air blowing on it during these times?

Eisen 1440EV, 5hp, Yaskawa v1000

Thanks.

 

[benmychree]

How, since we developed machine tools and commenced the industrial revolution, did we get along without such as frequency drives?
I suppose that one could fairly easily make use of some sort of fan or blower, although it may not be optimally effective with TEFC motors, but if one could drive the original fan with another motor at full operating speed, space permitting, it might work out satisfactorily.

 

[matthewsx]

I doubt it’s going to be a problem. Make sure the drive is tuned to your motor.

Definitive answer is likely to come from @mksj

John

 

[mksj]

The lathe was designed to operate over the speed range that it in the spec. sheet, so no additional cooling is needed. If it was needed, they would have installed a TEBC motor. They oversize the motor to run on a VFD over a wider operating range, the minimum Hz is usually 20, you can check the VFD display. Most TEFC (which is what comes in your lathe) do not have cooling issues until you get below 15Hz, a TENV does not require cooling as it relies on mass/fins to cool the motor and are usually good down to almost 0 speed.

Motor is already tuned from the factory, it is a factory installed Yaskawa drive. If there were concerns for thermal, they would have used a motor with T-stats and tied those to the VFD fault input.

 

[jareese]

Perfect - thanks Mark.