Stepper Wiring How To

This is the wiring diagram for the steppers I used on my project. It is outdated but still useful for others. Steppers can be found at &

Stepper Specs

Steppers should have the following: 5, 6, or 8 wires. 5-7 volts. 1.2 amps or less. 200 or 400 steps (1.8 degrees or .9 degrees). NEMA 23 or NEMA 17 frame size.

How To Wire Your Own Steppers

***The Yahoo group called scope-drive has a database of steppers that are found to be good for the system. That database also includes the wiring sequences for many different surplus stepper motors. It may prove useful to you. ****

Now, a simple way to figure out the wiring for steppers. If you don't care to solder led's or delve into wiring diagrams, or charts, here is a quick, simple and fast way to wire up the steppers.

Fist things first. The side of the 9 pin connector that has 5 posts: they are all connected. If you look on the pcb, you will see solder connecting all of those posts. Consequently, you can interchange all of them.

The other four pins are where the trouble is for most users. That is understandable, they confused the heck out of me too. Don't worry about it though, they can be figured out.
Here is how: from either end imagine they are labelled A, B, A- B-. This will help you figure out the wiring later on.

Now most people will have a 6 lead (wire) stepper motor. Few will have a 5 lead stepper. This procedure works for both. If you have 5 lead steppers, you only have one power lead and four others. A six wire stepper has 2 power leads, not one.
This exercise may help those of you who have them  anyway.

Get a Multimeter. You can beg, borrow or buy one very cheaply. You can find ohm meters too. Don't freak and think   "OH NO !! Electrical work, I'll shock myself, burn down the house, fry the laptop or the pcb" . You won't be going anywhere near voltage or do anything to fry ant part of the circuitry or yourself..

Set it to OHMS. Don't worry about which Ohm setting, just pick one that is ohms.

You will not hurt anything using the multimeter. There is no risk of shock, frying parts or anything of the sort. Just don't plug one of the leads in a wall socket with wet hands 8^)

Pick a wire. Make sure it has some of the actual metal wire showing on the end. {Make sure you strip all the ends of all 6 wires. You need an inch or so. } Hold it firmly to the black wire from the meter. Pick another and hold it up to the red lead from the multimeter. Make sure you have contact, metal to metal. Keep swapping out wires on the red multimeter lead until the needle on the multimeter moves. There should be two other wires that make the needle move if you have 6 leads (wires) coming from your stepper. These are the wires for a winding. You will label it a or b later on. For now just put something around the three wires (tape) to keep them straight. Test out the other three and make sure the needle moves as above.

Now you have both winding leads figured out. Leads are wires and there are two windings for a 6 wire stepper. Next step is to find the power wire from both sets of three. These are the wires that you will eventually connect to one or two of the 5 pins in a row on the 9 pin connector. Typically, the power wires are black and or white.

Here is how to get the power wires figured out. You need to set your multimeter to a ohm setting of X1. Mine has X1, X10 and X1k (100). The goal is to make the needle not peg to the right all the way when connecting two of the wires from the same winding lead. There should be a little room on the right when connecting two of the wires together.
The goal is to find the wire that when it is connected to the black lead of the multimeter, the other two move to the exact same place on the multimeter when connected to the red lead. There are only three choices for the power wire, but it is very important to get this right.

Three wires: white, green and green and white striped. When I hold the black lead from the multimeter to the green wire, I then hold the red lead from the multimeter to the white wire. The meter reads something (3 in this stepper). But when I change the red lead to the white lead, the meter reads xx (6 in this case). The green isn't the power lead. Same thing happens when I hold the green with a white stripe to the black lead from the multimeter and put the red lead from the multimeter to the green and white wires. The green and the green with a white stripe are not the power leads. When I hold the black lead from the multimeter to the white wire and touch the green and the green with a white stripe (not at the same time) to the red lead from the multimeter, the reading on the meter is the same. This means the white is the power lead. The other two are winding leads. They will go on two of the pins on the 4 pin side of the 9 pin connector.

Do the same for the other three wires. You should now have the two power leads figured out and the four wires for the 4 pin side of the 9 pin connector. Hard part is over now. Put the meter away, return it to the store, give it back to whoever you borrowed it from.

Now you can make a diagram that looks like this:

Wg---------winding lead, 4 pin side

W ----------power lead, 5 pin side

G-----------winding lead, 4 pin side
R-----------winding lead, 4 pin side

Bk----------- power lead, 5 pin side

Rw--------winding lead, 4 pin side

Rw=red with a white stripe

Gw=Green with a white stripe

Randomly pick one of these sets of three to be winding A and the other to be B

I choose R, Rw, Bk to be winding A, the others are B.

Make the diagram look like this:

Wg---------winding lead   ( B )

W ----------power lead

G-----------winding lead   (B-)
R-----------winding lead   (A)

Bk----------- power lead

Rw--------winding lead   (A-)

Now on the 4 pin side of the nine pin connector, you need to follow this order A, B, A-, B-  or B-, A-, B, A, either direction is fine.

Now if you picked the wrong A or B it does not matter. The only choices are in this order on the 4 pin side of the 9 pin connector:

R, Wg, Rw, G
Rw, Wg, R, G
R, G, Rw, Gw
Rw, G, R, Gw

or the reverse of each

The black and the white wires get connected to the 5 pin side of the 9 pin connector. Any two pins will do just fine.

I made a 9 pin connector with 6 wires coming from it that are about a foot long. 2 wires come from the 5 pin side and 4 come from the 4 pin side. That way, if I am careful, I can just manually twist the wires together and test them out.

Hooking up the wires incorrectly will not hurt anything if done for a short time (couple of minutes). All that will happen is the motor will buzz. What you are looking for is all three movements of the steppers to work, not well, just work with the default software settings. Hook up the pcb to the laptop and power and give your settings a try. Do use only 12 volts, (13.2 off the battery) no more, no less.

Once this is finished, it's time to set the variables for the steppers. In the control menu of scope, the ms parm item. This sets the tracking motion. The slewing motions are in the hsparms section of the control menu of Scope.exe.

If this is over your head to do, but you still want the order figured out, I can help. Look at the bottom of my pricing page. You will find my mailing address. Ship me the steppers and the return postage (and however much you want to add, if anything) and I'll figure out the wiring for you. Don't send me 8 lead steppers. They are over my head 8^)