Motor poles encoder and compatibility

Hi all! I got an ODrive 3.6 not too long ago and am now looking for an appropriate motor for my application. I calculated I’ll need about 3.2Nm nominal by 3000RPM and I want to use 48V. I found a supplier who can provide me a model with mentioned specs, it would be 1000W, nominal current 27.8A and peak current at 83.4A.

Thing is it’s an 8 pole motor. Also they provide a 2500cpr encoder, looks to be differential and with index line.

Would above be controllable with ODrive ? Is 8 pole alright and also is the encoder of high enough resolution ? (is differential supported ? otherwise I can make it single ended myself)

Hope anyone can help me out!

Thanks & best regards,


1 Like

Nothing wrong with an 8 pole motor. More pole-pairs ~= more torque, lower speed (lower kV), and less cogging. Fewer pole-pairs = higher RPM/V, lower torque, more cogging, in general.
But with more pole-pairs, you need higher resolution in the encoder.
I use a 21 pole-pair motor with a 16k cpr encoder = 780 encoder counts per pole-pair, which is plenty of resolution for good torque control, and just about enough for cogging compensation (anticogging) to work.
With 4 pole-pairs and 2500cpr you have 625 counts/pole-pair which is broadly similar.

27A / 83A peak is ideal for ODrive.

Differential encoders are not supported. You will need to convert that to single-ended with a RS422 receiver chip.

1 Like

Hi Tom, thanks a lot for that confirmation, I’ll order a sample and try it out!

1 Like