Machsupport Forum
Mach Discussion => Mach4 General Discussion => Topic started by: striplar on February 18, 2021, 03:11:39 PM
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Has anyone experienced this? I've got two separate spindle that I can use on my mill, each with their own frequency converter.
In recent weeks I've had both run up to maximim RPM while running a program, even though there's no speed change in the program. That's oversped and destroyed three spindles now that I'm going to have to re-bearing. I can't afford for this to keep happening?
Is this unique to my setup? Any ideas what might be causing it?
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I forgot to mention that I'm running V4.2.0.3804
I don't know if this other thing I've noticed has anything to do with the issue.
Every so often I'm getting an ESS communication error that throws a dialog box even though the machine keeps running. I just answer No to the question about reconnecting and nothing ever seems to happen.
I didn't get this error when the problem occurred though.
Does anyone know why this is happening either?
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I can't help, but you might go ask at the warp9td.com forum and see if Andy can help with the ESS error. He might be able to direct you on the VFD/spindle thing, too.
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Ok, thanks for that, I'll do that.
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I've downloaded the latest version of Mach4 4.2.0.4612 and the ESS plugin V270 and now it doesn't enable the drives even though all of the setup screens are unchanged. It did work with 4612 before I installed the plugin V270 though.
However, now I've put it back to V231 plugin and restarted the ESS, it doesn't work any more.
However, it is throwing a Mach4GUI debug window on exit which generated the attached dump file.
On the initial boot with V270, it threw the error...
Can't read value of key 'HKCU\Software\Mach4' (error 2: The system cannot find the file specified.)
However, it no longer produces that error.
Any ideas?
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How are you converting the signal into analog for the drives? You must have some sort of PWM to analog converter ? We need to know more about your hardware to help with this .
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Sorry, yes I'm using a CM106 board which does the PWM conversion to give me 0-10V for the analog reference to the motor drive.
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Have you put a meter on the output without the drive connected so you can see if your getting a variable voltage ?
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I've just managed to get the machine working with the latest Mach4 V4612 and the ESS V270, it lost some of the pin configurations and I had to put them in again.
The spindle responds correctly to the analog signal for 99% of the time. However, it suddenly ran up to maximum speed for no reason on several occasions. That's what I'm trying to rectify because it's so destructive.
Can ESS communication issues cause this to happen? For the first few years I ran this software I didn't get a single error reported. Now I get them every few hours. Up until today, I was running the software combination at the beginning of this post. I've only brought both up to date in the hope that it's a bug that's been fixed.
I'm deeply suspicious of Windows updates, is it possible that this is what's causing the ESS errors?
I'm still getting the debug dump at the end of each session, is that something that you can help with? I'm afraid it means nothing to me, I have no idea why it isn't happy. It never happened with the old software combination.
I've gone over all of the spindle wiring and there's nothing loose. I deliberately disconnected the Analog reference to the drive, and it slows to a stop rather than running away, so it's not that.
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That sounds like a serious and expensive issue - definitely not normal behavior. I feel you need to consider a few potential causes like,
1, Since both spindles exhibited the same problem, the common factor is likely your frequency converters.
2, If your CNC controller is sending incorrect speed commands, this could force overspeed.
3, If your system uses spindle encoders or tachometers, check if encoder cables damaged.
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except I would guess the 'common' between two inverters is in this case the ESS and Mach4.. I would doubt that both working inverters would suddenly exhibit the exact same issue. Receiving communication issues between the ESS and Mach4 is not a good start and probably indicative to something else causing the problem. Could be noise, could be a connection, could be something else you may have running on the pc.. could be some issue that's causing the program (Mach4 internals) to hang somewhere which could cause communication errors. That's certainly a more difficult issue to troubleshoot. I've had this issue (communication) and it turned out to be a monitoring program that was basically doing nothing and sitting in the background. Took a while to diagnose but eliminating it corrected the problem. The overspeed might be corrected by this. As a safeguard temporarily you might be able to set the max speed on the inverters lower so this won't destroy the bearings. :o
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Hi,
how have you programmed the VFD's?. All VFD's have parameter that determines the max frequency and therefore the max motor rpm.
Surely you have programmed the VFD's to some max and safe frequency such that even if the CNC controller/program were to runaway no damage can be done?
Craig
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Have you looked for a wiring problem, in particular a dodgy ground connection?