stepper motors run one-way only ? connections ?

[pavel59]

Hello to everybody,
after a long time I started again playing with mach and some hardware.
I'm trying to re-assemble an old machine I made a few years ago, just to give it to a friend. All the components I'm using have already worked well, but now something must be wrong and I'm having troubles in running my motors.

The breakout board has been made by a friend, it's optocoupled and it worked flawlessy in the past.
The drives are professional one from RTA (an italian brand) and give up to 6A and run on 35 to 72V and may drive down to 2000 microstep.
The motors are 8 wires bipolar motors from Astrosyn 34PM-C101-09 3.2V 4.3A/phase

The machine is fixed gantry style with ballscrews.

The problem I'm having is that the motor runs only one way, it ignores the direction change. If I invert a couple of pairs then it runs the other way, but still one-way.

I'm sure I'm missing something somewhere, but due to the long time pased I can't remember what could be the issue and where to look for.

Any one has an idea about the possible fault ?

I think something may be wrong in the wiring, since the original cables have been lost during the relocation of my workshop last march.
I rewired the connectors and it's possible that I'm doing something wrong.

I will split again the electronic box and double check all the connections.

Thank you in advance for your kind and valuable help

Paolo

[Torchhead]

One of the down sides of engineering your own design from odds and ends and home built interface cards is that you are the only person that can fix it.

As long as you have the DIR signal for and axis (Config/Ports&Pins/Motor Outputs) mapped to the right pin (which is up to the design of the BOB) then should get direction change.

99% chance of a wiring mistake or bad pin mapping if it does it on all the axis.

[Filobus]

Hello.
I've got a very similar problem.
If you find your solution, can you please write the solution here for us?
Thank you

[sawmiller]

on my system ( pinmo drives A3977 ) the problem was that my power leads into the driver card had a loose solder joint, it would go one way, but not the other. once i found that , and resoldered, no problem ( i think it was the ground wire that had the loose joint.
dan