Re: RPM on steppers & StepServos
For speed you need voltage. The problem with your driver is not the current, but the fact that the operating voltage is maximum 40V. You can't run that driver with anything higher than that. Current is only important for the torque, so assuming you will not have high load you won't need high current. Generally speaking NEMA23 motors are better with high speeds than NEMA34.
On the temperature, I'd not add any fans, though I have heard about somebody using fans, I never understood why. If your driver is OK then heat should not be an issue. Motors can get very hot and that is normal. Temperatures between 60-70 degrees C are not unusual and you can't really feel that with your hands. Measure it if you are worried, but note that high heat may not be caused by the current but also by a badly designed driver. I don't know the driver you plan to use, but I'd go for the very common DQ542MA or a better, newer digital version of it. The one you have looks like based on the Toshiba chip, which generally is not the best for your purpose.
Re: RPM on steppers & StepServos
[QUOTE=imitheo;2063668]As i expected, the drivers rate the total peak current, so the stepper is rated on amps/phase, actually amps rms/phase. So my motor, that is rated 4.3A/Phase, should be run at a driver that is capable of reaching 12A. THATS A LOT :/[/QUOTE]
No, nooooo, no no. Goodness! No!
[QUOTE=A_Camera;2063688]For speed you need voltage. The problem with your driver is not the current, but the fact that the operating voltage is maximum 40V. You can't run that driver with anything higher than that.[/QUOTE]
Good catch, I didn't check the driver voltage specs.
Re: RPM on steppers & StepServos
[QUOTE=NIC 77;2063772]
Good catch, I didn't check the driver voltage specs.[/QUOTE]
I didn't check the specs just the picture and it says 9-40V. Regarding specs... that's another issue... also I have no idea what the maximum frequency is for that driver, maybe too low to run it fast anyway. A driver which is not speced for at least 200kHz is not a very good one for speed running.
Re: RPM on steppers & StepServos
[I]'ve switched to StepServo's AKA Integrated Closed loop steppers[/I] I'm using JMC-motor.com iHSS57-36-20 NEMA 23 2nm 36v steppers ($124ea). I feed them 36vdc, step, and dir from my Break Out Board from Linuxcnc. So my control box is basically a power supply for the spindle 48v and steppers 24v, PWM spindle speed control for my DC spindle and the parallel breakout board. I have lots of room now in the box. The steppers run about 5-15F over ambient temperature and get a bit hotter when really running them. Since they have encoders in the with an integrated driver, they're not sitting there with 100% holding current all the time, just enough to not free wheel and it actively holds position. It's well worth the little extra money to try some. In NEMA 23 and 24 they have 1nm, 2nm, and 3nm. In NEMA 34 I believe they go to 35nm for hybrids. I'm getting 1500rpm at 24v with mine which is good for 141 inch a minute (236in/min theoretical)