PMDX 424 with mix of servo's and stepper

[Mike Abbott]

I've got my X, Y, Z axis all working great with the 424 and Gecko G320's.  I'm adding an A axis that's based on a Nema 23 motor and a Gecko 203V drive.  I get power to the motor just fine and it locks into position but when I go to move the axis nothing is happening.  I'm fairly certain the wiring from the 424 to the 203v is correct (it's 3 wires and I have them color coded so unless I became color blind, it's correct).  Is there some setting I'm missing in the plugin setup (or is this possible to mix servo's and steppers). 

I did some basic troubleshooting and even tried a different stepper motor which behaved the same.  The pmdx diag screen says it's outputting step/dir signals so I'm a bit mystified on what's going on.  Any help would be appreciated.

Mike

[Bob at PMDX]

Are your servo drivers G320 or G320X?

If you really have the older G320 drivers, the issue is the Step/Dir Common inputs on the two different Geckodrive drivers.  The G320 requires +5V on the "COM" terminal.  The G203V requires GROUND.  There is a way to work around this:

(1) Connect the G320 "COM" terminals to the "com" terminals on the PMDX-424 motor connectors along with the step and direction wires on (I'm guessing) J7, J8 and J9.

(2) Connect the G203V "COMMON" terminal to the PMDX-424 "GND" terminal on connector J12 (the "Outputs" connector) or on J13 (the "Encoder" connector).

(3) Go into the SmartBOB plug-in configuration dialog, click on the "Motor Config" tab and set the "Step/Dir Common" to "+5V".

You should be all set.

Bob

G320 COM is +5V
G320X COM is +5V or GND
G302V COM is GND

[Mike Abbott]

Well got all excited and went and tried that based on your explanation (which is quite good) and no luck.  I'd discovered the +5v common when setting up the G320's (original one's) when I got everything working.  I even tried just setting the common to 0v in the pmdx settings just to see if the drive would turn and it didn't (knew the x,y,z wouldn't work but wanted to get the new stepper to move at least once).  Power is there, motor and gecko are warm (I have it current limited to ~2.5A), green light on the g203v, shaft with no power spins fairly free, with power it's locked in place.  So, question is, is there some diags or logs I could send or should I just get a drive that will deal  with the common voltage in a similar fashion to the g320 like a g201x?

Mike

[Bob at PMDX]

Yes, a G201X should work using the same common polarity as the G320 drivers.  However, the G203V also *should* work presuming it is wired correctly with the common going to a ground reference on the PMDX-424 and not the step/dir "com" terminals.  So before you go buying another driver, try a couple of things:

(1) What version of PMDX-SmartBOB plug-in are you running?  You can go to the "Diagnostics" menu and select the PMDX SmartBOB.  Our diagnostics dialog will display the Mach4 build, plug-in version and firmware versions.

(2) If you are running plug-in version 0.41.205 or higher, go to our plug-in configuration dialog and click on the "Feature Config" tab.  Are the 3A and 3B motor outputs enabled or disabled?

(3) Re-check the wiring from the PMDX-424 to the G203V, and tell me here what those connections are, just to be sure.  For example, presuming you have the G203V on the PMDX-424 "Motor3a" terminals (J10), you would say something like:
          J10 step to G203V step
          J10 dir to G203V direction
          J12 LGND to G203V common

(4) Disconnect the PMDX-424's Z axis step & dir terminals from the Z axis G320 and connect the G203V step & dir terminals where the Z axis used to be.  Now try jogging the Z axis and see if the G203V moves the motor.  Restore the normal Z axis step & dir wiring to the original G320.

(5) Create a profile package and either post it here or email it to me at bob at this domain.  To create the profile package, go to the 'Help" menu and select "Support", then select "Package Current Profile".  Save the file somewhere that you can find it, and then post it or email it.

Bob

[Mike Abbott]

Got it working.  After your last suggestions I remember messing with the feature config and motor 3 enable/disable.  Basically I was looking for anything to do with motor 3 to get some response from the motor and had left it as disabled.  After correcting that and moving the common to one of your suggested grounds it works fine.

Appreciate your help and patience dealing with my operator error.

Mike

[Bob at PMDX]

Glad to hear you got it running!

Bob