Author Topic: 424 and SmartBob -- getting it all to work  (Read 3203 times)

soupdragon

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424 and SmartBob -- getting it all to work
« on: August 13, 2019, 09:22:09 AM »
Bought Mach4 and a 424+407 (build3804) and spent a week trying to get it to work but with no luck.
Cant get 'Ref all Axes' to work. X does home but on hitting the limit switch maching retracts and goes into 'Disabled' mode and stops.
Goto work Zero doesn't work at all - no movement, machine goes to 'Disabled'
Probing - Z moves but on touching plate maching goes to 'Disabled' and that's the end of that, same with corners.
Havn't even bothered with the 407.
Viewed a post which recommended reverting to build 3390. Did that and the only bit that changed was the the 'Goto Work Zero' works, all else the same.

So it seems that the software keeps tripping into 'disabled' mode.

Thought I was upgrading from my Duet board but now I think I'll revert to it...



12strings

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Re: 424 and SmartBob -- getting it all to work
« Reply #1 on: August 14, 2019, 12:17:55 AM »
When you try homing and the system goes into "disabled", what message(s) do you see in the Mach4 status line (lower left of the wx4 screen set).  Or click on the "history" button to see all of the messages, not just the most recent one.  You can also turn on Mach4 logging (Diagnostics menu, then "logging") to see even more information.  The PMDX plugin usually displays some kind of message if it has to disable Mach4.  Post the contents of the "history" and "logging" windows here.

There could be noise coupling into your limit switch inputs, or maybe even the EStop circuit.  How do you have them wired?  Do the limit switch wires run near any high current power wires - including a VFD? spindle motor? Plasma torch???????

Can you drop down to a single motor and home/limit switch, and disconnect everything else?  If you have an EStop switch, replace it with a short jumper wire (or the PMDX-424's original shorting clip).  Then try homing that one motor/axis.  Do you still see this problem?

soupdragon

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Re: 424 and SmartBob -- getting it all to work
« Reply #2 on: August 14, 2019, 09:42:19 AM »
FINALLY solved the 'Disabled' message by lowering the current on my stepper motors and reducing the pulse rate to 400.
Set the homing on Y axis to both motors 1 & 3 and allocated the same limit switch to both motors. Now Ref all axes works but I still can't get 'return to home' to work.

Probing still a problem  Set the prep distance but can't see how to set the distance the probe is to move after the Prep move until it should touch the surface. (Prep move + test move = total probe movement)

soupdragon

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Re: 424 and SmartBob -- getting it all to work
« Reply #3 on: August 14, 2019, 11:46:29 AM »
Probing the centre of a circle.
Works intermitently. Will start to move but will stop on contact with one of the 4 surfaces and give the message below.

X axis is moving to a requested machine position.
Y axis is performing a touch move.
Machine just hangs there until reset.

Will perform a complete touch action once in approx 5 or 6 attempts.

12strings

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Re: 424 and SmartBob -- getting it all to work
« Reply #4 on: August 14, 2019, 11:12:54 PM »
I haven't tried to use probing in several years.  When last I looked at it, there was talk of issues with the Mach4-provided probing scripts that didn't properly handle cases where the probe would just touch, but then bounce back to "not touching" when the motor stopped.  Part of the probe code would see the probe touch, then the second part would check again and see the probe not touching and fail.  I have no idea if this was the real issue, and if so if it has been addressed in build 3804.

And reducing the current to your motors making the problem appear less often definitely sounds like an electrical noise issue.  Though getting the history and logger window contents will help show whether that is the case and might even shed light on your probing issue.  Meanwhile, if you haven't already, get your high current wiring as far away as possible from your limit switch wiring.  No long parallel runs of power/motor wires and limit switch wires.

soupdragon

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Re: 424 and SmartBob -- getting it all to work
« Reply #5 on: August 15, 2019, 05:37:29 AM »
All my high current (motor) wiring is run in double screened cable.
Probe wiring is completely separate from all other wiring and short (18" or less)

soupdragon

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Re: 424 and SmartBob -- getting it all to work
« Reply #6 on: August 15, 2019, 05:40:49 AM »
Anyway it's exactly the same setup and wiring that I used with my Duet3D board which worked 'straight out of the box' with no issues. Worked perfectly!

soupdragon

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Re: 424 and SmartBob -- getting it all to work
« Reply #7 on: August 16, 2019, 03:31:43 PM »
Well thanks to those who replied. However not bring able to sort out even simplest of problems and having spent 2 weeks tryng to do so I have reverted to my Duet3D board, which incidentally, works fine.
If anyone wants a cheap 424 + 407  then contact me - they are yours.

12strings

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Re: 424 and SmartBob -- getting it all to work
« Reply #8 on: August 17, 2019, 12:42:59 AM »
Your prerogative, mate.  I can sympathize with wanting/needing to get the machine running again and the frustration of not getting something to work.  But a "simple" problem?  Noise issues (IF that is what this was) are never simple except in hindsight.  Double shielded cable for motor wiring sounds nice, but depending on your grounding scheme it may or may not help.  Or wiring that defeated the isolation on the PMDX-424's inputs.  Or something totally different (for those Monty Python fans).  The log files might (emphasis on "might") have helped figure out where the issue is/was.  But no guarantees.

soupdragon

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Re: 424 and SmartBob -- getting it all to work
« Reply #9 on: August 29, 2019, 06:02:14 AM »
Orderd a new encloseure and will rewire and resite and have another go. Let you know what happens but may be some time.

soupdragon

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Re: 424 and SmartBob -- getting it all to work
« Reply #10 on: September 08, 2019, 07:53:53 AM »
Well, rewired (using mainly the existing cables) and reworked all the earthing for the cable shields + a new encloseure and ------ IT WORKS!!
Obviously very sensitive to noise as my Duet wasn't.
Anyway thanks for the help and for encouriging me not to give up.
Hope this assists others.