How hot do your stepper motors get?

[klick0]

I have 2 stepper motors, initially I bought the cheap japan servo's from hobbycnc.com, I also have an oriental vexta PK268B (I think that's right).

The hobbycnc servo gets real hot real fast. Currently I have a slighty strange driving mechinism, a stepper controller from controlanything.com, basically it's just 4 mosfets, and over the serial line you tell it which ones to activate. A 12vdc power source, 15 amp. Not sure how those differ from something like a geckodrive. Regardless I have the hobbycnc servos configured at half power, only using one phase at a time, to keep heat down. But they still get very hot.

The oriental motor I run at full power (2 phases at a time) and it gets warm.... and then after a long time gets kinda hot but not anything like the japan servos.

I'm just worried that somehow i'm running them to hot, I don't want to damage them... plus after the machine runs for some time I start missing steps like crazy, but i'm not sure if it's because my motors are overheating or my drivers.

I did recently get a G210 drive, which I plan on switching the whole system over to, but I don't have a heatsink/fan for the G210 drive so I havne't tested it much, as it starts missing steps after 15 seconds without a heatsink.

Ross

[ger21]

If it gets hot really fast, the current might be set too high.

Most steppers are rated to run up to 100°C.

What voltage and current are you running the Gecko at? I've heard of people running them without heatsinks and them not getting that hot. In 15 seconds its so hot it's missing steps??

[ger21]

It sounds like you don't have the current set resistor on the Gecko and it's delivering all the current it can. Those HobbyCNC motors are 1-2a, aren't they?

[klick0]

You are right, I don't have the resistor set on the driver, actually that's another question I had. Basically I was trying to get a 8.2k resistor to limit it to 1amp, to see what that would do. I didn't have 8.2k laying around but after looking at the manual, it appeared (maybe i'm wrong) that basically the resistor could be about anything and they had a formula to figure out how much current would put out. I just guessed and put a 10k resistor on it and it still pulled full load, and actually didn't do the standby thing with the resistory, it stayed at high load. I couldn't figure out if there was something else I needed to do or not to get that to work?

Ross