Hot stepper motors at idle

[GeneMpls]

All my stepper motors run about 125F when sitting still for a bit. I assume that
that is normal... but is it a problem? I run this PRS when I have time- while I am doing another job in the next room and sometimes it sits idle for a couple hours.
Thanks Gene

[bleeth]

Not a problem at all.

[tlempicke]

Just to expand on Daves answer a bit

That would be a normal operating temp for a stepper.

Steppers run the hottest when they are not in motion.

[Ed Scherer]

I happened to have my IR thermometer handy while I was running a job on the Desktop today and remembered this thread. After about 30 minutes of running a couple of jobs, the Z-axis stepper was running quite hot: 223 °F (106 °C). Could cook on it. :)

IIRC, while it was idling before I started, but after I first turned it on and left it for awhile and then did a spindle warm-up, it was about the same as in the original post in this thread.

https://lh3.googleusercontent.com/-_jdNJuHJLPc/UjyVDJRWZCI/AAAAAAAAekw/OsvUrXqIp9E/s640/2013-09-C1-0112.jpg (https://lh3.googleusercontent.com/-_jdNJuHJLPc/UjyVDJRWZCI/AAAAAAAAekw/OsvUrXqIp9E/s0/2013-09-C1-0112.jpg)

[richards]

Oriental Motor stepper motors are rated with a temperature rise of 80 degrees C over ambient, so 195 is about maximum. The auto-current reduction feature found on newer stepper drivers will keep the motors at a cooler temperature, but will also reduce standby holding torque. I've never worried if the IR reading was 80 C or less.