How do I ID the leads on a 8-wire stepper?

OK, so here's my problem: Bought these from China for a customer but it turns out the leads are not correctly matched to the coils according to the wiring diagram. I know my customer is not the problem because the other torque sizes work fine and he knows what he's doing when it comes to wiring motors.

So I managed to find the correct pairing in parallel config by trial and error which I confirmed by being able to rotate the shaft by hand for each of the four pairs. But that leaves me unable to arrive at how to order the pairs to A A- B B- to connect to the drive.

What baffles me most is that when I check the resistance of the pairs the multimeter shows the rated resistance of series config. In fact, all the of the eight leads give this same value. And no matter how I pair them--same thing.

Any help/advise would be greatly appreciated.

Could you show me your motor's brand and its model?

let's call the pairs for this moment 1- 1+, 2- 2+, 3- 3+, and the last 4- 4+
connect 1- and 2- together and 1+ 2+ together if you can rotate the motor free, that you found the A pairs and even the right - and + connection.
If rotation is not free, connect 1- and 2+ together and 1+ and 2- together. Running free, you found the pair, but - and + of the 2 needs to be reversed.
If it's still not rotating free, connect 1- and 3- together and 1+ and 3+ together and so on. following this you should find the connections

Quote:

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Originally Posted by Toinvd

let's call the pairs for this moment 1- 1+, 2- 2+, 3- 3+, and the last 4- 4+
connect 1- and 2- together and 1+ 2+ together if you can rotate the motor free, that you found the A pairs and even the right - and + connection.
If rotation is not free, connect 1- and 2+ together and 1+ and 2- together. Running free, you found the pair, but - and + of the 2 needs to be reversed.
If it's still not rotating free, connect 1- and 3- together and 1+ and 3+ together and so on. following this you should find the connections

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Thanks for this. The idea intrigues me. I have four pairs. But I have no way of knowing within a given pair which one is + and which one is -.

It doesn't matter if you call them + or - if all coils have the same Ohm resistance i'ts fine then you don't even have to take care for coil1 or coil2 l
Take one pair and label this first pair as A1- and A1+ ( don't mind which one is + or - )
Find the pair which you can connect in parallel to this such that the motor rotates free ( all other 4 wires disconnected ) and when found, label the one connected to A1- as A2- and the one connected to A1+ as A2+
Now do the same for the other two pairs, label one pair as B1- and B1+
put them in parallel such that the motor rotates free and label the one connected to B1- as B2- and the one connected to B1+ as B2+
If you connect your motor to a driver and it runs in the wrong direction, just reverse one side. like B1- will be B1+ , B1+ will be B1- , and B2- will be B2+ , B2+ will be B2-
Only reverse one side otherwise the motor will again run in the wrong direction.

Quote:

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Originally Posted by Toinvd

It doesn't matter if you call them + or - if all coils have the same Ohm resistance i'ts fine then you don't even have to take care for coil1 or coil2 l
Take one pair and label this first pair as A1- and A1+ ( don't mind which one is + or - )
Find the pair which you can connect in parallel to this such that the motor rotates free ( all other 4 wires disconnected ) and when found, label the one connected to A1- as A2- and the one connected to A1+ as A2+
Now do the same for the other two pairs, label one pair as B1- and B1+
put them in parallel such that the motor rotates free and label the one connected to B1- as B2- and the one connected to B1+ as B2+
If you connect your motor to a driver and it runs in the wrong direction, just reverse one side. like B1- will be B1+ , B1+ will be B1- , and B2- will be B2+ , B2+ will be B2-
Only reverse one side otherwise the motor will again run in the wrong direction.

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I'll give it a whirl, thanks!