MESA Cards to Panasonic MINAS A6 Driver Troubleshooting Help

Hello all,

I hope I posted this under the right category/topic.

I am currently working on a project to create a 3D printer. I have been stuck on this problem for a while now, and any help is greatly appreciated!

For the x, y, and z axes on the 3D printer, I am using the Panasonic MINAS A6 drivers to control my motors. I have tested these drivers and my servo motors together using the Panaterm software to ensure that they are compatible and are working. I was able to jog all three motors using the Panaterm software and a mini-USB cable.

Here is more information about the Panasonic MINAS A6 drivers (note that I am using the SE type, which does not have the x2, x3, or x5 ports):
www3.panasonic.biz/ac/e_download/motor/f.../minas-a6_manu_e.pdf

These Panasonic MINAS A6 drivers have an x4 port (shown in the figure attached below) that I have made pin-by-pin connections to. I soldered these connections and made sure they are well-isolated, and I tested these connections using the continuity function from a multimeter.

The x4 port on the driver connects to my MESA boards. The MESA board that I am using is the 6i25-7i76 PNG kit, which contains a MESA 6i25 card, a MESA 7i76 card, and a DB25 cable that connects the two cards. The MESA 6i25 card is plugged into the host PC which is running LinuxCNC. The MESA 7i76 card is connected to the MESA 6i25 card via the DB25 cable. The MESA 7i76 card is also connected to the x4 port of the MINAS A6 driver with the following configuration: 

1. x4 pin 3 (PULS 1) -> STEP+ (on 7i76)
2. x4 pin 4 (PULS 2) -> STEP- (on 7i76)
3. x4 pin 5 (SIGN 1) -> DIR+ (on 7i76)
4. x4 pin 6 (SIGN 2) -> DIR- (on 7i76)
5. x4 pin 7 (COM+) -> 24V
6. x4 pin 29 (SERVO ON) -> GND
7. x4 pin 41 (COM-) -> GND

On the MESA 7i76 card, the step +/- and the direction +/- are connected to TB2 on one of the step gens. Both of the MESA boards are properly powered: the MESA 6i25 is powered by the host PC and the MESA 7i76 is getting 5V from the MESA 6i25 through the DB25 cable and 12VDC from an external DC power supply for field power.

I have created a LinuxCNC PNC configuration for my system. The only physical connections on the MESA 7i76 card is the x4 port of the driver and external DC power for field power. No limit switches are connected yet, and all the field I/Os are left open. Only 1 step gen is connected at the moment to try to get it working first.

I have used an oscilloscope to probe the step +/- pins on the MESA 7i76 card when jogging the LinuxCNC PNC configuration to observe the output. There seems to be a step signal on the scope; however, the motor does not move when jogging through the LinuxCNC interface. Could this be due to the PNC configuration setup variables (e.g., step on time, step space, etc.), improper connection between the MESA 7i76 card and the Panasonic MINAS A6 driver, or not connecting other motors/limit switches?

I am totally lost on where the problem could be, and have spent months trying to troubleshoot this issue. Again, any help is truly appreciated!

Thank you!

Hello tommylight,

Thank you for your reply!

I have checked to make sure that the drive is set for position mode (specifically, the parameters 0.01 and 0.05 on the drive were set through Panaterm).

Also, the motor is not locked. When the drive is enabled, I was able to jog the motor using the Panaterm software and a USB cable.

Hello tommylight,

Thanks for the advice!

I finally figured out that my DC power supply was acting weird and that there was no current being drawn. I fixed that and now I am finally able to jog my motors through LinuxCNC!

Now a small update on that - I am only able to jog my motors in 1 direction (both plus and minus buttons on the interface move the motors in 1 direction).
Could this be a PNC configuration (.hal/.ini files) issue?

Sounds more like a wiring issue

I would check that the direction signal at the driver ( measured between sign1 and sign2 )
reverses polarity when you jog in different directions

Hello PCW,

Thank you for the quick reply!

I checked using a multimeter that the signal does change polarity when jogging in different directions.

I also double-checked my wiring to make sure that the direction signal +/- go to the appropriate ports on the 7i76 board. Could it possibly be a drive issue, perhaps setting a specific parameter?

Hi tommylight,

Thank you for your reply!
I am using servo motors instead of stepper motors, would that site still apply?

I will test different step/dir configurations. If it is possible could you please provide more info regarding setting the modes in LinuxCNC whenever you have the convenience.

Yes, a drive set to up/down (CW/CCW) mode would behave the way yours are.

If this is the case, you can either change your drives input mode to step/dir
or change the Mesa stepgen mode to up/down (step_type 1)