Need Help!- 1 Driver 2 Stepper Motors, is it possible will it work?

[guy2b1]

Is it possible to connect 2 stepper motors to 1 stepper driver so that when the motor rotates at the same time? I have 12Volts Stepper Driver planning to use small stepper motors gathered from inkjet printers.

[jhowelb]

Get ready for blown drivers.

[nophead00]

Yes you can wire them in parallel as long as the drive circuit has enough current to drive two in parallel.

In this example I wired 4 in parallel to move a table up and down http://hydraraptor.blogspot.com/2008...nt-z-axis.html

A video of it working here: http://hydraraptor.blogspot.com/2008...ntraption.html

[guy2b1]

Thank you nophead00, that was very interesting you wired 4 stepper motors to 1 stepper driver do you have a picture were I can see how you wired those stepper motors to 1 stepper driver? Im a newbie and I have no electronics background but I am very much eager to learn more about electronic stuffs. I was thinking of creating a RepRap machine or 3D Printer similar to yours for my hobby

[amishx64]

The wiring is simple. Take all the some color wires - if the motors are all the same - and wind them together then attach to your driver as you would for one single motor. IE: Red and Red, Green and Green, etc.

If they aren't the same you have to at least make sure the step size and coil resistance are all the same. The resistance can be compensated for with resistors, but you don't want a one stronger and one weaker motor.

To see step size and resistance, read the label. Resistance can also be found by using an ohm meter across a coil.

If the motor is Unipolar the diagram will look like this:

----------------------- | --------------------------------
| Wire 1 ---------- Center Tap (Wire 2) ---------- Wire 3 |
| |
| Wire 4 ---------- Center Tap (Wire 5) ---------- Wire 6 |
----------------------- | --------------------------------

If the motor is Bipolar (4 wire), the diagram will probably look like this:

----------------------------------------------------------
| Wire 1 ----------------------------------------- Wire 2 |
| |
| Wire 3 ----------------------------------------- Wire 4 |
----------------------------------------------------------

OR If you have an 8 wire bipolar motor:

----------------------------------------------------------
| Wire 1 ----------- Wire 2 ...... Wire 3 ----------- Wire 4 |
| |
| Wire 5 ----------- Wire 6 ...... Wire 7 ----------- Wire 8 |
----------------------------------------------------------

Measure resistance by going across the same wires on each motor with an Ohm meter. Label all the wires as so they represent one of the diagrams above. This will make your motor and driver connections easier. Once you are done labeling wires, hook wire 1 to wire 1, wire 2 to wire 2, etc.

Oh, and to make sure you don't blow the driver do the following calculation:

1/Resistance_stepper1 + 1/Resistance_stepper2 = 1/ANS

or Resistance_stepper1^-1 + Resistance_stepper2^-1 = ANS^-1

then take Solve V = I * R
where V = power supply volts
I = current in Amps
R = Resistance of the two motors as found above (ANS)

Ex: 12 = I * 4
I = 3 Amps (You want to make sure your driver can supply this much current in Amps or more.)

Ask if you have questions.

[nophead00]

guy2b1,
Sorry I don't have a picture of the wiring but amishx64 has explained it very well. My motors are bipolar so they have four wires. I connect the wires of the same colour to each other and then connect them to the controller as a single motor would be connected.

They take about 0.5A, so the total current required is 2A.

[guy2b1]

Thank you very much nophead00 and amishx64

Currently I tested 1 Stepper Motor 1 Stepper Driver using 12Volts 10Amps Power Supply. I already tested 3 sets of Stepper Motors and Drivers (1 Stepper Motor 1 Stepper Driver per set) for my CNC Machine design using 12Volts 10Amps power supply for my X,Y,Z axis. I plan attaching 2 stepper motors 1 stepper driver for my Z axis to make it stronger for heavy loads. Also im experiencing that my motors are very hot to touch by hand is this normal temperature for these stepper motors?

Will try and test attaching 2 to 4 Stepper Motors to 1 Stepper Driver. I hope this work.

These are the stepper motors I gathered from Inkjet, dot matrix printers. Problem is there is no label indicating coil, volt, ampere details of each stepper motor. Only the company named Minebea, Sanyo, Mitsumi indicated in the sticker labels. Im guessing these motors can run in 12Volts as well.

[amishx64]

Well yes, the smaller and lower resistance motors will get hot @ 12V. Just make sure it doesn't get hot enough to melt the plastic insulation off the wires.

Before you just start connecting motors, you need to get the coil resistance as I mentioned and calculate the current draw or you could blow a driver.

Oh, and to make sure you don't blow the driver do the following calculation: 1/Resistance_stepper1 + 1/Resistance_stepper2 = 1/ANS or Resistance_stepper1^-1 + Resistance_stepper2^-1 = ANS^-1 then solve V = I * R where V = power supply volts I = current in Amps (you don't know this yet) R = Resistance of the two motors as found above (ANS) Ex: 12 = I * 4 I = 3 Amps (You want to make sure your driver can supply this much current in Amps or more.)

Again like I said match your motors to the diagram types. I see both bipolar and unipolar in your pictures.

Take some pics of the labels and note the number of wires on each motor. I'll help you identify them and maybe determine which ones you should use together.

[guy2b1]

Here are the pictures of all my stepper motors labeled. At the moment I have no access to ohm meter to measure the coil resistance in my home area, but will try to ask our neighbor electrician about this if he can measure. Thank you very much for all your help

[guy2b1]

Im also thinking what if I connect 1 stepper driver with 2 identical stepper motors rotating at the opposite direction to make the work load stronger especially when attached to a CNC gantry to move any Axis. Is it also possible aside of wiring with same colors?

[amishx64]

Originally Posted by guy2b1 Im also thinking what if I connect 1 stepper driver with 2 identical stepper motors rotating at the opposite direction to make the work load stronger especially when attached to a CNC gantry to move any Axis. Is it also possible aside of wiring with same colors?

Oh yes, that is totally possible, and a great idea. I like it. However you need two couplers per thread / axle / screw mechanism.
.
.
OK, so lets get down to business.

Here, I will discuss only the first two motors. I will make a new post for the others because this is so long.

Your steppers labeled #1 (Astrosyn x3) and #2 (Astrosyn x1) are both 6 wire. That means you will have a internal coil setup as so for both motors:

----------------------- | --------------------------------
| Wire 1 ---------- Center Tap (Wire 2) ---------- Wire 3 |
| |
| Wire 4 ---------- Center Tap (Wire 5) ---------- Wire 6 |
----------------------- | --------------------------------

It is likely you may be able to use the first motor type that you have three of and the second type if the degree step and resistance are the same. Use an Ohm meter for resistance testing. You can try to use a pair of pliers to move the spindle 1 NOTCH on each motor. If the notch increment seems the same, the motors most likely have the same step size. Judgment call.

///////////////////////////////////////////////////////////////////////////////////////


For motor type #1 (that you have three of) the labels say 24V, 2A. That means if you want to calculate resistance calculate the following: V = I * R for your motor. V = 24, I = 2, R = ?.
24 = 2 * R
R = 12 Ohms (Omega symbol)

So your motor diagram will look like so:
----------------------- | --------------------------------
| Wire 1 ---12Ω--- Center Tap (Wire 2) ---12Ω--- Wire 3 |
| |
| Wire 4 ---12Ω--- Center Tap (Wire 5) ---12Ω--- Wire 6 |
----------------------- | --------------------------------

The first thing you need to do is find what wire colors match up to which numbers on my diagram. You can do this without an Ohm meter by trying one wire on GND of a PSU and another on +12V. If the motor budges, then you have a connection. However, you'll need one later on to determine what is a center lead. Another way without using an Ohm meter would be to do this:


GND ------ small light bulb ------- random motor wire 1
+12V --------------------------- random motor wire 2

When you take any two wires from your stepper motor, you have a chance that they will be connected inside. There are a two possible connections.

1. One possible connection could be a half coil connection, yielding a 12 Ohm connection. Ex in diagram: Wire #1 --> Wire #2, Wire #2 --> Wire #3, Wire #4 --> Wire #5, Wire #5 --> Wire #6.
2. Another possible connection could be a full coil connection, yielding a 24 Ohm connection. Ex in diagram: Wire #1 --> Wire #3, Wire #4 --> Wire #6.

The object of the light bulb is to determine whether you have a full coil connection or a half coil connection. The bulb will glow brighter with a half coil connection (less resistance, 12 Ohms) than with a full coil connection (more resistance, 24 Ohms). In this way you can use a light bulb to figure out which wire color corresponds to what number on the diagram.
If the bulb does not glow, that means you have a dead bulb or have one wire from a different coil that the other wire. Remember, there are two coils in this motor.


///////////////////////////////////////////////////////////////////////////////////////


Once you have your wires numbered, you have a choice of what configuration you want to use the motor in.
You can use this motor as a unipolar motor by connecting wires #2 and #5 to 12V on your power supply and #1,3,4,6 to your driver.

OR

You can use this motor as a bipolar motor which will generally be stronger (more force / torque). With this you will connect wire #1,3,4,6 to your driver.

to connect one in forward, and one in reverse you would do the following:

For unipolar: Center leads wire# 2, 4 still connect to the PSU for both motors.
You would simply reverse the connections on the second motor.

(Motor_1, wire_1) & (Motor_2, wire_6) ---> Driver pin 1
(Motor_1, wire_3) & (Motor_2, wire_4) ---> Driver pin 2
(Motor_1, wire_4) & (Motor_2, wire_3) ---> Driver pin 1
(Motor_1, wire_6) & (Motor_2, wire_1) ---> Driver pin 1

For bipolar: Don't use wire #2,5. Tape it off and make sure no shiny wire is showing to short out anything.

(Motor_1, wire_1) & (Motor_2, wire_3) ---> Driver pin A+
(Motor_1, wire_3) & (Motor_2, wire_1) ---> Driver pin A-
(Motor_1, wire_4) & (Motor_2, wire_6) ---> Driver pin B+
(Motor_1, wire_6) & (Motor_2, wire_4) ---> Driver pin B-

Notice for bipolar drivers, the pins are labeled with a letter and a (+) or (-).

I REALLY hope this helps. I'll explain the rest of the motors in my next post tonight. Ask if you are confused about anything.

[amishx64]

OK, here I go again.

Motor number three may be your odd man out. This can work ONLY as a unipolar motor.

Diagram:
---------------------------------------------------------
| Wire 1 --------\````````````````` /---------- Wire 3 |
|```````````````Center Tap (Wire 2)````````````````|
| Wire 4 --------/````````````````` \---------- Wire 5 |
---------------------------------------------------------

See the difference? Do use this you need to find what wire is the center lead and tie that to your +Vcc (+12V). You can use my light bulb method with this one, but an Ohm meter would be easier. There is only one combination that will yield a brighter bulb (lowest resistance) than all the others. Once you have the brightest bulb setting, you know which wire is the center one.


///////////////////////////////////////////////////////////////////////////////////////


Steppers #4, #5, #6, #7, and #8 are all bipolar ONLY (4 wires). Because you have three of these, you may want to use your 6-wire steppers in a bipolar configuration, NOT using the center tap (wire #2 and #5).

Here is a bipolar internal diagram. Pretty simple.

----------------------------------------------------------
| Wire 1 ----------------------------------------- Wire 2 |
| |
| Wire 3 ----------------------------------------- Wire 4 |
----------------------------------------------------------

You need an Ohm meter to determine the resistances of the last couple motors. There is no other info on the stickers. My bet is they would be 1.8 or 2.7 degrees.

To connect to a driver one forwards one reverse:
(Motor_1, wire_1) & (Motor_2, wire_2) ---> Driver pin A+
(Motor_1, wire_2) & (Motor_2, wire_1) ---> Driver pin A-
(Motor_1, wire_3) & (Motor_2, wire_4) ---> Driver pin B+
(Motor_1, wire_4) & (Motor_2, wire_3) ---> Driver pin B-


The only resistance info you give me is on motor #6. 2.4 Ohms. This thing is gonna get hot at 12V. I recommend not using this one too much or at all.

The last motor, #9, is a brushed 2 wire motor. This is not going to do you any good for this project. Keep it anyway though. To use, connect one terminal to GND and one to +5V or +12V. It'll spin pretty fast. You can find this motor's resistance with an Ohm meter too.

Hope this helps. Feel free to ask about anything I didn't explain properly.