Need a little help? with 8 wire stepper motors total newbie

[stevef12005]

Hi everyone, i know this must have been asked before but i'm stuck,

i have a Nema 23 equivellent stepper motor they are 8 wires & this is where i get stuck?

A:BLU/WHT
A':BLU
C:RED/WHT
C':RED
B:GRN/WHT
B':GRN
D:BLK/WHT
D':BLK
i need to wire them to a board that is 1A 1B 2A 2B this is the bit i'm stuck with, i know you can wire them serial or parallel but what wires do you connect to each other.

Should i connect the BLUE & the RED and GREEN & BLACK and then use the BLU/WHT AS A1 & RED/WHT AS A2 ALSO THE GRN/WHT AS B1 & BLK/WHT AS B2.

i hope this makes sence if someone who knows what there doing that could explain

cheers steve

[andypugh]

I know this is a long time after the original post, but I have been struggling with what is quite possibly exactly the same motor. (3Nm NEMA 23 M60STH88-3008D)

Part of the problem is that the data sheet is wrong. If you wire it as shown then it doesn't work. This is because the start/end of some windings has been switched, so when you wire them together they are in opposition rather than addition, so no net effect. This was very puzzling as there were step voltages going to the motor and large currents were flowing, but there was no effect at the motor (no rotation, no stall torque, no change in cogging torque, no humming or whining. Nothing)

I finally figured it out by energising the coils one at a time using a current-limited desktop PSU. (half an amp is plenty)

This is what I found.
Each coil has a plain colour at one end and a white stripe on the other.
The blue and red coils are a pair, the green and black coils are the second pair.

By connecting the pairs in series and finding which way gave holding torque and which way gave zero torque I figured out the following:

Blue is the start of BlueCoil. Blue/White is the end of BlueCoil
Red/White is the start of rRedCoil. Red is the end of RedCoil
Green is the start of GreenCoil, green/white is the end of GreenCoil. Black/White is the start of BlackCoil, Black is the end of BlackCoil.

(I am using BlueCoil etc in an attempt to be clear, as A B C D are already used, confusingly)

It is entirely possible that your motor is wired differently, so you may still need to do the experiment

I need a serial connection, as I have only 2.5A controllers, but have 27V. That means end of blue connected to start of red and end of green connected to start of black. So I connected:
end of BlueCoil to start of RedCoil (Blue/White to Red/White)
end of GreenCoil to start of BlackCoil (Black/White to Green/White)
1A to start of BlueCoil (Blue)
1B to end of RedCoil (Red)
2A to start of GreenCoil (Green)
2B to end of BlackCoil (Black)

If your controller can supply 4A then you will get far better performance in parallel (the same stall torque, but much better torque at speed according to the performance graph):
1A to start of BlueCoil and RedCoil (Blue and Red/White)
1B to end of BlueCoil and RedCoil (Blue/White and Red)
2B to start of GreenCoil and BlackCoil (Green and Black/White)
2B to end of GreenCoil and BlackCoil (Green/White and Black)

Hope this helps somebody.