4th and 5th axis configuration with PMDX-126

[Max]

Hello everyone,

I have Doughty drives (B/C drives) and I am trying to add 4th and 5th axis to CNC router. I wired B drive to KL-4030 driver and then to PMDX-126. I use Mach3 software. I mapped pins in Mach3. However, B drive only rotates in CW direction, no matter whether I input positive or negative values in Mach3. Attached is the image of connections I made to BoB to J1. What am I doing wrong? This is new to me, so bear with me please.

Thank you.

[12strings]

It looks like you have the step wire in the screw terminal for parallel port pin 9, and the dir signal in the screw terminal for parallel port pin 8.  Is that how you have Mach3 configured?

When you jog this axis back and forth, you should see the LED next to the "pin 9" terminal turn on for one direction and off for the other direction.  If you can't jog the axis and look at the PMDX-126 at the same time, you can jog one direction then stop and then look at the LED.  Jog the other direction, stop, and look at the LED.  It should remain lit after jogging one direction, and remain off after jogging the other direction.

Look at all of your Mach3 settings (motor step/dir and all output signals.  Make sure nothing else is configured to drive port 1 pin 9 (presuming that you are on the primary PC parallel port).

Are you sure you have the wires securely in the screw terminals?   I believe the 126 uses "rising clamp" screw terminals, which means you need to lower the clamp, insert the wire and then raise the clamp.  If the wire is squeezed under the clamp it will (or may) have only intermittent contact.

If the motor still only runs in one direction, remove the DIR+ wire from the screw terminal and put it in the "PC+5V" terminal.  See which way the motor runs.  Then move the DIR+ wire to the "PCgnd" terminal.  Does the motor run in the opposite direction?  If it runs in the same direction  check all the connections on your motor driver.

[Max]

It looks like you have the step wire in the screw terminal for parallel port pin 9, and the dir signal in the screw terminal for parallel port pin 8.  Is that how you have Mach3 configured?
Yes, that is how Mach3 is configured.
When you jog this axis back and forth, you should see the LED next to the "pin 9" terminal turn on for one direction and off for the other direction.  If you can't jog the axis and look at the PMDX-126 at the same time, you can jog one direction then stop and then look at the LED.  Jog the other direction, stop, and look at the LED.  It should remain lit after jogging one direction, and remain off after jogging the other direction.
LED next to pin 9 is very dim. LED next to pin 8 is on in one direction and off in the other.
Look at all of your Mach3 settings (motor step/dir and all output signals.  Make sure nothing else is configured to drive port 1 pin 9 (presuming that you are on the primary PC parallel port).
Nothing is configured on these pins other than axis A.
Are you sure you have the wires securely in the screw terminals?   I believe the 126 uses "rising clamp" screw terminals, which means you need to lower the clamp, insert the wire and then raise the clamp.  If the wire is squeezed under the clamp it will (or may) have only intermittent contact.
I am sure. Double checked it.
If the motor still only runs in one direction, remove the DIR+ wire from the screw terminal and put it in the "PC+5V" terminal.  See which way the motor runs.  Then move the DIR+ wire to the "PCgnd" terminal.  Does the motor run in the opposite direction?  If it runs in the same direction  check all the connections on your motor driver.

I does turn other direction.

[12strings]

OK, so we have the LED for pin 9 glows dim while jogging.  That is to be expected of the step signal.  The LED for pin 8 is on when jogging one direction and off when jogging the other.  Also what is expected.  When you manually connect the DIR+ signal to PC+5V or PCgnd the motor changes direction, as it should.

So we are left with (possibly) the pin 8 output somehow isn't driving the DIR+ signal.

Test #1: Repeat the "manually connect DIR+ to PC+5V and PCgnd" test, this time recording which direction the motor moves (or which direction the axis moves) when DIR+ is +5V and which direction when DIR+ is GND.  Now leave the DIR+ wire unconnected.  What direction does the motor turn.  Finally, re-connect the DIR+ wire to the pin 8 terminal.  Attempt to jog both ways.  What direction does the motor turn?

Test #2:  If you have a volt meter or multi-meter, jog the axis one direction, then measure the voltage between the pin 8 screw terminal and the "PCgnd" terminal.  Jog the axis the other way and measure the voltage on the pin 8 screw terminal again.  What readings do you get.  They should be near 0V and somewhere between 3.8V and 5V according to the 126 user's manual.

Test #3: Look at the bottom side of the 126 board and check the solder joints on the screw terminals that you have the wires connected to (J1).  Do all the pins on J1 look like they have nice, clean, smooth solder joints?

[Max]

Test #1: Repeat the "manually connect DIR+ to PC+5V and PCgnd" test, this time recording which direction the motor moves (or which direction the axis moves) when DIR+ is +5V and which direction when DIR+ is GND.  Now leave the DIR+ wire unconnected.  What direction does the motor turn.  Finally, re-connect the DIR+ wire to the pin 8 terminal.  Attempt to jog both ways.  What direction does the motor turn?

DIR (+) in +5V turns CCW
DIR (+) in GND turns CW
DIR (+) unconnected turns CW
DIR (+) in pin 8 terminal turns CW

Test #2:  If you have a volt meter or multi-meter, jog the axis one direction, then measure the voltage between the pin 8 screw terminal and the "PCgnd" terminal.  Jog the axis the other way and measure the voltage on the pin 8 screw terminal again.  What readings do you get.  They should be near 0V and somewhere between 3.8V and 5V according to the 126 user's manual.

+Jog = 0.6V
-Jog = 0.6V. Terminal 8 LED is ON.

Test #3: Look at the bottom side of the 126 board and check the solder joints on the screw terminals that you have the wires connected to (J1).  Do all the pins on J1 look like they have nice, clean, smooth solder joints?

All connections are clean. Images are attached.

Thank you. Sorry it took me so long to do the tests.

[12strings]

From your test #2 results: you measured then same voltage (0.6V) after jogging both directions, even though the LED turned off and on?  Hmmmm.....

Do that test one more time, paying attention to how bright the "Pin 8" LED is when it is turned on.

Then remove the wire from the "Pin 8" screw terminal, and then fully tighten the screw terminal.  Jog both directions and again measure the voltage on the "Pin 8" screw terminal to the "pcgnd" screw terminal.  And see if the brightness on the "Pin 8" LED changes (is it brighter or dimmer than when the wire was attached).

Next, try swapping the wiring for the motors on "Pin 8" and "Pin 9" with the motor on "Pin 6" and "Pin 7" (the next set of screw terminals.  This means your black wires are now connected to J2 (pins 6 and 7).

Try jogging the axis that is mapped to pins 8 and 9.  Does that other motor turn both directions?

Try jogging the axis that is mapped to pins 6 and 7 (which should be the motor that previously only turned CW).  CAn you jog it both directions?

[Max]

From your test #2 results: you measured then same voltage (0.6V) after jogging both directions, even though the LED turned off and on?  Hmmmm.....

Do that test one more time, paying attention to how bright the "Pin 8" LED is when it is turned on.

Then remove the wire from the "Pin 8" screw terminal, and then fully tighten the screw terminal.  Jog both directions and again measure the voltage on the "Pin 8" screw terminal to the "pcgnd" screw terminal.  And see if the brightness on the "Pin 8" LED changes (is it brighter or dimmer than when the wire was attached).

Jog (+) = 0.68 V CW. LED off
Jog (-) = 0.68 V  CW. LED on and it is bright.

Wire removed from pin 8 and the screw fully tightened.

Jog (+) = 0.03 V  LED is off
Jog (-) = 0.00 V LED is on, same brightness as with wire in pin 8.

Next, try swapping the wiring for the motors on "Pin 8" and "Pin 9" with the motor on "Pin 6" and "Pin 7" (the next set of screw terminals.  This means your black wires are now connected to J2 (pins 6 and 7).

Try jogging the axis that is mapped to pins 8 and 9.  Does that other motor turn both directions?

Yes, it does turn both directions.

Try jogging the axis that is mapped to pins 6 and 7 (which should be the motor that previously only turned CW).  CAn you jog it both directions?

No, it only turn in one direction.

[12strings]

I'd say contact PMDX and asking about sending the board in for repair.

P.S. The voltage readings don't make sense given the LED changes (on and off).  All the more reason to contact PMDX directly.