Motors not moving on my ord bot

[apipe]

I just built an ord bot hadron with a azteeg board and surestepr drivers and Sparkfun steppers from here https://www.sparkfun.com/products/10846. I tested my motor to board connections with a multimeter and each coil tested at 2.6 ohms where it plugs into the azteeg board. The driver v ref is set to 0.5 v and I tried a higher current but it did not seem to make any difference.

Here is a video of the x axis attempt to move


Here is the y


I tried slowing the speed and no difference. I am using a atx 600 w supply. I also tried a 12 gel cell.

Any suggestions?

Alyssa

[royco]

Alyssa,

It looks like you have miss wired your motors. Can you check that pair black and green go to 1A and 1B (or 2A and 2B).

If you have endstops connected, remove it.

You may also upload the test code found here to check movement of the motors.

http://files.panucatt.com/X3_test_code.zip

[fma]

I think it is a current issue. Try to decrease the current: the pololu may switch off because of too much current...

[AndrewR]

Definitely a motor wiring issue. They need to be wired like this. Red-Blue-Green-Black or Black-Green-Blue-Red (or two others that I won't mention for the sake of simplicity).

[bdring]

Sometimes motors do this with only one coil hooked up. Do the motors make a clicking sound when they are not commanded to move? That is a sure sign of overheating.

[Cre8ivdsgn]

Try looking to see if one of the connections are not made. Or perhaps the output of the driver is not working on one of the phases. We (royal "we")see exactly this kind of thing when a wire harness is worn out and one of the four conductors going to the stepper motor fatigues and breaks.

Its possible the motor might be mis-wired. Drivers can be labelled for connections A, B, C, D or A, A-bar, B, B-bar (I don't know how to "over" line versus underline but the symbology is A, NOT A, B, NOT B). So the two phases (typically) are A,B and C,D (or of course A, A-bar and B,B-bar). If you use a meter, each complete phase will be the max reasistance (below 20 ohms or so) you find across a pair of wires. I spell it out this way because you can have six and eight wire motors as well (well, with the eight wire motors you will end up with four pairs and then you need to figure out if you want torque or speed optimized motor performance to determine the wiring order). With four-wire motors there are no choices to make and this method works.

For eight wire motors, you really need to find the exact wire color codes given by the manufacturer of the motor for best results. (Oriental drove me nuts for a while when I tried to use "common sense" to figure out the pairings, but a color change from what I expected had me chasing my tail.)

If the motor is running the wrong direction, simply swap the wires on ONE of the phases. And document it!!!

Disclaimer - its been many years since I gave this much thought. Someone can improve on this I'm sure.

[apipe]

Thanks for the suggestions. I found the problem - it was a combination of the documentation for the azteeg board and my wiring to follow what I thought it was supposed to be. The azteeg docs labels the wires on the motors:

1A 1B 2A 2B

I assumed that it was a A coil and a B coil so connected the pairs 1 3 and 2 4 when they meant the coils were 1 and 2 and the wires were A and B. I moved the wires around and it worked great.

Thanks for the help and the documentation could be a little clearer.

Alyssa

[royco]

Alyssa,

Good to hear you got it working. That got me too the first time.

I checked the wiring diagram again and it seems to be labeled correctly(1B 1A 2A 2B). I think I even got the color coding for your motors right . Maybe I'll place the drawing of the coil on the motors to show the pairings.

Thanks

Roy

[bdring]

I personally think Roy's schematic is beautiful. I am switching my schematic style to emulate his look for my plasma cutter.

This is the stepper symbol I am using for the my plasma schematic. Even if your wire colors don't match it is easy to figure out.

[Cre8ivdsgn]

Bart:

Looking at the illustration (and perhaps this was your intent) I can't help but think of a phone jack or RJ45 plug. Better yet, using a cat5 cable.
For NEMA 17 motors at least, CAT 5 cable should be good enough. And the twisted pair nature (as long as you wire the individual stepper coils to the appropriate pairs) would do wonders for noise reduction, I would think.

Jamco sells the RJ45 connectors for something very reasonable. (Yes, I know cat5 is not RJ45 but at this instant I don't remember what the appropriate receptical size is for CAT 5 cable.)

I can just imagine an Azteeg board or somesuch with the recepticals going right to the motors. This would go a long way to eliminating wiring errors.

Just a thought.