motor wirieng

[cueshark]

i have searched on here for 3 or 4 hours trying to find out how to figure out which wire goes where on bipolar & unipolar motors when you can not find a wirieng diagram. i have found that you can use a ohm meter to figure some or all of it out, but i did not see what the ohm meter readings mean. in other words if it is 0 between 2 wires what does that mean? or what do other readings mean? any help learning how to figure this out would be appreciated. thanks in advance in case anyone tries to explain this to me. greg

[gar]

070418-1129 EST USA

cueshark:

The coil resistance will be low. For example: 1/2 to 1 Ohm. Your meter may not allow you to read low values like this easily.

An alternative approach is to use a series resistor of maybe 5 Ohms at 10 W
to apply a current to a motor coil. From a 6 V battery the short circuit current is 6/5 A.

If you measure the voltage drop across the coil and the current to the coil, then you can calculate the resitance from R = V/I . Or from Rcoil = 5ohms series resistor*Vcoil/(6volt source-Vcoil) .

With 1 A current you may get a noticable spark when you open the circuit. You might use a reverse biased diode across the coil to prevent this high voltage generation on breaking the circuit.

If you have 8 wires, then there 4 independent coils. If 6 wires, then 4 coils with each pair having a common wire.

.

[niclatrique]

If your bipolar stepper has 4 wires, think of it has two separate wires going in and out of a box. When you try which wire goes with the other, you will try any possible combination.

Look at the attached PDF.

Do you agree there is no electrical connection between A and C or A and D ?
In this case, do you agree that the resistance should be really high or even infinite or OL OverLoad as your meter would say.

Do you agree that there is an electrical connection between A and B and between C and D ?
In this case, do you agree that the electrical resistance between A and B or C and D would be low or near 0 as you meter says.

For a six wire stepper it's like if there was a center tap exactly at the center of each winding.

In this case, do you agree that the resistance between A and E or B and E will be very near the half the value of the resistance between A and B?

If you want to know which wire is which, write down all wire colors and try every possible combination and note the values. Thereafter you'll be able to know which wire is which.