Phase resistance of bipolar stepper (wrong?)


I recently purchased a bipolar stepper motor which I'm planning to run with a Big Easy Driver. On the datasheet, it says phase resistance = 1.65ohm +/- 10%. However, when I measure the resistance, it reads 2ohm.

I have double checked the part-no printed on the motor (JK42HS48-1684) against the datasheet, and it really is wrong.

Then my questions:

  1. May it simply be that I'm doing something wrong?
  2. Does it even matter as long as I adjust the current limiting pot on the BED?
  3. Should I expect a difference in the motors performance (and why?)

Best regards,
Aleksander Hansen

Unless you have a very good resistance meter I would put the difference down to measurement error.
The important thing is to set the proper current limit so that the motor does not overheat. Just set the current to whatever the motor datasheet says and ignore the resistance measurement.

The Thread stepper motor basics may be useful.


What does you meter say when you touch the probe tips together?

For a low resistance value you need a Kelvin measurement (4-terminal) for accuracy,
so the high current path is separate from the voltage sense wires.