I have a stepper motor datasheet that doesn’t have peak current. It shows drive voltage 5V and coil resistance per phase of 10 ohms. Does this mean that peak current is 500mA (V = I x R)? I assumed this was the case, but I have another datasheet for a different motor that has a drive voltage of 24V and a coil resistance of 5.8 ohms. However, it specifies a peak current of 1A as opposed to about 4A based on Ohm’s law.
Hi.
Generally, stepper motor specifications are given with the rated voltage corresponding to the voltage at which the resistance of the motor will cause it to draw the rated current. 24V seems pretty high to be the rated voltage of a stepper motor, but it is a common input voltage for a stepper motor controller system. Could your second motor have a built-in control system? If you post the datasheets for your motors, I might be able to offer more insight.
-Claire
Thanks for the quick response. 24V is the rated voltage and there does not appear to be any controller system.
Here’s a link to the specs:
http://www.mitsumi.co.jp/latest/Catalog/compo/motor/m49sp2k_e.html
Unfortunately, that datasheet did not give me a better idea of why the rated voltage and current for that motor do not correspond with Ohm’s law. My best guess is that the rated voltage listed there is a maximum recommended voltage.
In another thread you mentioned testing a motor with incrementally increasing current to find a good operating point. That method seems reasonable.
-Claire