Author Topic: Setting up PMDX-107/VFD with PMDX-126 and relays  (Read 9776 times)


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Re: Setting up PMDX-107/VFD with PMDX-126 and relays
« Reply #15 on: May 23, 2020, 10:37:47 AM » poster (I think)
I too am having a somewhat similar situation, but yet also a little unique.
I’m utilizing a PMDX-126 with the DIP configuration: 1-8 all on except 7 is off;
 married with the PMDX-107 with its DIP configuration: 1,2,5 & 6 are off, 3 &4 are on.

My VFD (Teco) is solid; utilizing an toggle (by relay or SS) and speed (RPM) by analog input (10VDC)
All has worked well under a different BOB and controller.
Also, when I push the 107’s self contained “Test” button, everything works fine.
However, when I manually click the spindle button on my Mach4 interface or enter the appropriate
code in the MDI (stating speed) my “spindle on” (PMDX-107 out-pins, 4 & 5, I get only a quick energization
at k1 (relay and light) and of course the light at pin 5, then nothing until I make a second attempt at starting
the spindle.
Again, pushing the self-contained “Test” button on the 107 has the spindle performing as it should.

...not sure if I was to post here (couldn’t find where else to go)
Thanks in advance....


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Re: Setting up PMDX-107/VFD with PMDX-126 and relays
« Reply #16 on: May 28, 2020, 10:31:41 AM »
So, to expand on your DIP switch settings:
PMDX-126: Run in "normal" mode without charge pump, no aux feature enabled.  I can't tell what sw7 and 8 do without knowing how JP1 and JP2 are configured.

PMDX-107: Normal mode, SSRs are "run" and "direction", ignore "charge pump OK" signal, fast PWM filter and 10V output range.

Since you mention "K1", I presume you have the PMDX-126's relay somehow involved with the spindle operation?

So backing up a bit: how do you have the PMX-126 connected to your PC?  One of the PMDX SmartBOBs?  A SmoothStepper?  Something else?

When you try to turn on the spindle form Mach4, are you entering a speed and fwd/rev command (i.e. MDI commands "Sxxx" then M3 or M4)?  And have you configured the "Spindle" tab in the configuration screen to set your actual max RPM?