Author Topic: PMDX 407 connected to pmdx 422 How to configure analog speed control (Mach4)  (Read 3483 times)

rgdesign

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Hi I purchased the pmdx 407 speed control to use the analog output for speed control. I currently have a manual rotary potentiometer that is connected to my spindle drive (Driveblok).
 I have connected the board to my 422 board in accordance with the instructions and have been able to verify that the board receives power and works in PWM mode.

I need some advice on how to configure Mach4 to communicate with the 407 analog outputs.

Thanks,

Romesh

Bob at PMDX

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I need some advice on how to configure Mach4 to communicate with the 407 analog outputs.

The basic steps are outlines in section 5.2 of the PMDX-407 QuickStart Guide.  However, re-reading it we left out a couple of steps, plus in the latest release of our plug-in the spindle configuration has moved to its own tab in our plug-in configuration dialog.  So here is a revised copy of the steps from section 5.2:

* Start Mach4Hobby with the SmartBOB-USB and PMDX-407 connected.
* From the top menu bar, select "Configure" and then "Plugins..."
* Find the PMDX-SmartBOB-USB and make sure it is enabled, and select its Configure button
* [REVISED] In the PMDX plugin dialog, select the "Spindle Config" tab at the top (or in older versions of the plug-in, the "Feature" tab)
* Select the PMDX-407 in the "PWM Spindle Speed Control" section
* Set the minimum spindle speed as a percentage of maximum. Most spindles will have a
speed below which they have insufficient torque to be usable (risking tool breakage because
the tool stops turning) and below which the motor?s internal fan will not keep the motor cooled
properly.  This is a number from 0 to 100, and is usually in the range of 0 to 25.
* If you do not have a spindle speed sensor, you will likely find it handy to enable the ?Report
calculated spindle speed to Mach4 as actual spindle speed? so that the on-screen readout (if
provided) indicates approximate spindle speed.
* Click ?OK? at the bottom of the two dialog boxes to close them.

New steps:
* Go to the "Configure" menu and select "Mach".
* Click on the "Spindle" tab
* In the first row (labeled "0" - zero), fill in the minimum and maximum spindle speed.  Note that even though Mach4 supports 20 different spindle ranges, by default it uses range #0.  It requires custom-written Lua code and/or a custom screen set to select a different spindle range.
* Optionally, you may fill in the spindle accel and decel times.
* Leave the feedback ratio at 1, this is only used when there is a sensor on the spindle to determine actual spindle speed and the SmartBOB does not yet support this feature.
* Set the "Max Spindle Motor RPM" to the max RPM that you want your spindle motor to turn.  This should reflect any pulley ratios between your motor and the actual spindle quill.  So this is the motor RPM when your spindle is at the speed that you entered in the "MaxRPM" field.
* Leave the "Step/Dir Spindle Axis" set to "None"
* Leave the "Enable Step/Dir Spindle Rigid Tapping" un-checked.
* Click on OK

You now should be able to enter a desired spindle speed using an "S" command and then  start the spindle either with an "M3" command or by clicking on the "Spindle CW" button and see an analog voltage on the PMDX-407's outputs.

Bob
Engineering Hell: Everything's right and nothing works.
Bob's Corollary: If everything's right and nothing works, double check your assumptions.

rgdesign

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Hi Bob, Thanks for the quick response, instructions and information. I followed them and am able to now control speed using the analog outputs.

Thanks again,

Romesh