Here come the Hot Stepper!

[frankwilliams]

I have noticed that when I am surfacing my table my steppers for the axis I am srfacing along get really hot. I mean like burn your skin hot. They are the 7.2 gear reduction motors and I am running at 6ips move speed. Any body else find a similar result or do I have a problem? All input is appreciated.

Thank You

Frank

[richards]

Stepper motors run hot when they are moving constantly and fast. A stepper motor can have a 80-degrees C temperature rise (100-degrees actual temperature maximum) before they're beyond their ratings.

50-degrees C is too hot to hold for more than a few seconds, but it is well within the stepper motor's safe zone.

I'm currently running a temperature test on some motors that were sent to me. I'm having a hard time getting the temperature above 55-degrees C, even when the motors are wired bipolar parallel and run at 12-ips with a 50% duty cycle. The duty cycle seems to be the important parameter.

On my PRT-Alpha, I surfaced the table at 12-ips with a 1.5" cutter. The maximum depth was just 0.075", so the load was light. The 7.2:1 Alpha motors got warmer than usual, but not hot enough for me to ever get out the infrared thermometer.

[frankwilliams]

Thank You Mike,

That's exactly what I wanted to hear! I wasn't sure what the operating temp limits were for these motors and they are running at almost %100 duty cycle when I surface, so this all adds up. Just can't help but get nervous when they are too hot to touch.

Frank

[kubotaman]

Frank, I asked about the same question a month or so ago. Here is the link. You will find some good info as to your question in it.

http://www.talkshopbot.com/forum/showthread.php?t=12221