Stepping motor temperatures?

I’m curious what should be expected for the amount of heating that the stepping motors typically exhibit after a couple of hours of operation.

Using an inexpensive laser thermometer, I measured the surface temp of mine this morning. The results seem kind of intriguing, and I’m wondering if any of you folks think there might be an issue that I need to deal with.

First, please note that the two x motors and the two y motors are from Ryan’s store. However, the z motor is different because at the time of purchase Ryan only had 4 motors.

So, both of the motors on the y-axis were running about 40C. On the x-axis, the one at the far end (large y) was also about 40C. However, the one on the near end (small y) was at about 30C. The z-motor was about 30 C also.

At the time of measurement, the machine had been working for about 2 hours. Over several measurements over a few minutes, the temperatures were apparently stable.

And, finally, the measured difference between the x-motors was definitely real–it was obvious to the touch.

So, my questions are 1) are these temperature ranges satisfactory? and 2) what phenomena could be causing the 10C difference on the x-motors? (I’m not concerned about the z-motor–it’s operating completely in a different regime.)

As a side note, the 8825’s were calibrated during assembly to be at about 0.7 volts. And, there is a fan blowing on all three drivers. I’ve not checked those temps because they are inside a case.


Series, parallel, dual endstop (individually) wired? Sounds like individual and the drivers are a tiny bit off.

Under 50C is pretty safe (they can handle more but the parts can’t), I probably run mine at 35C. No need to push the limits as there are diminishing returns.


Pretty massive difference between 0.7V and 0.74V, just to clarify.

Sorry. I should have mentioned that info These are wired without the dual end stop, so they are wired in pairs. (serial?). That’s why I found it odd that the two motors on the same driver would be that much different.

Is there any possibility that the belt tension could change the load enough to cause a temp difference? Obviously, I’ve tried to make that as uniform as possible, but that’s all by feel, so who knows?

The only obvious difference is the extra wire that crosses through the 2’ wide bed, but the fact that on the other axis they are identical seems to negate that issue.

In the meantime, is dropping the driver voltage slightly the way to reduce the temperature?

Perfect that is the only way that makes any sense. That means they are individually powered (and wired not serial or parallel) and yes the temps will vary because of it. When energized I bet the meter will show a difference at the pot.


Yes. Just get it close, there really is no difference in terms of moving the machine, the hotter one is a bit stronger but you should never skip a step anyway.

Sorry but now I am confused. This unit does NOT have dual endstops. It uses the wiring package that you refer to as “serial” in your store. That is, the two x motors are driven by a single driver on the controller, and the y motors are driven by another, single driver. I thought that being individual meant that each motor was directly connected to it’s own driver. Thus, there is nothing to measure that would be the different between the two motors that vary in temperature.

What am I missing?

Can you put up a picture of how you have it wired please.


Take the belts off and double check both sides are actually turning under there own power as well.