Trying to get a Mighty Viper VMC 950 running again - old control repair / retrofit?

Hello everybody, Ive been banging my head against a 12,000lb paperweight for a little bit and have come to a crossroads. We are trying to decide to either fix the existing controls or retrofit. I would have already gone the retrofit route but it has mitsubishi drivers which everybody says are proprietary.

Machine is a Mighty Viper VMC 950, 20x40 3 axis mill, 20 position tool changer, 1999ish and some stupid low hours. By low I mean all the paint inside is still intact. Its Meldas or Meldas Magic running on a 486 w/ windows 95.

Machine worked great 2 years ago. It was running small jobs here and there, mostly aluminum. It went dormant for a while as other business ventures were pursued but are now needing the machine but after dusting it off we discovered some major problems.

All of the parameters were wiped out of the NC card. After a few days of messing with it, restoring parameter backups, formatting the card, restoring again, kicking the machine, and apologizing to it we have finally gotten it to run some simple programs, but we are unable to run anything more than moving the table around.

Unit goes into alarm when trying to toolchange. (first, toolchanger is off, but thats expected) The spindle wont index.

This weekend we are going to try to restore again but doubt that will work. We might even type in our paper copy of the parameter file to import but even then that is a shot in the dark. Instructions are non-existent and we havent had luck with the manufacturer in the past. They just want to sell a new hard drive to us but thats not where the problem is. Also Im not even sure if the NC card has some electronic problem or not.

Thats what brought us to retrofitting. We looked into that, going the Centroid route, or Mach3, but the problem is the servo drives are the mitsubishi ones that run SSCNET from what I gather so I would have to replace the drivers, which exceeds the price of just replacing the mill. (And us being a startup without a definite "this will make money" a retrofit north of $10k is hard to swallow.)

Does anybody have any tips or pointers? For now Im hoping to get the existing controls working, at least until I can get this thing printing money.

If its been sitting for years, the stuff I do is go over every sensor and switch in the machine. Clean and inspect contacts. Then cycle all the contactors of and on couple of times. Cycle hydraulic solenoids manually from the plunger. Kick and swear and say couple of prayers if that might help.
After that check relays if any are buzzing and what not.
Hope this helps.

Marko

The Viper is a good hunk of Iron. I had a Viper, I forget the model number but it was a 40X20 box way machine with the Mitsubishi Meldas control, My guys loved that control. Max RPM on that machine was 7500 RPM and that machine could hog steel man.

You could spend a boat load of money on a retro fit or you could spend a fraction of that getting a service guy to come in and restore the parameters and system back to the original configuration. If you have the machine moving but it's getting hung up at places like a tool change I would say you are pretty close and may just need some settings changed.

CNC Systems of Kennebunk Main was our dealer you could start by giving them a call. I am sure they could hook you up with the right guy in your area.

I would stick with what you have until I was sure there was no hope for getting it back in shape.

If I ran across a viper in good shape at the right price i would like to have on in my shop.

Good luck

Make Chips Boys !

Ron

Sounds like you need to re-load the ladder program. I have no idea how that is stored or loaded on the Meldas Magic control, but it is easily done on the other Meldas controls either by RS-232 or from an SRAM PCMCIA memory card.

It may be that the ladder is stored on the hard drive that the MTB is trying to sell you.

Ok here is a quick update for how far we got today.

We have a dozen or so backups but using file comparison for the all.prm (parameters) and ladder file I have 3 groups of files. Most files from 2012 on are identical. in 2014 2 parameters changed (to allow rigid tapping). there is a 2002 file which appears to be the original file for the machine because it matches a paper printout that came with the machine (unknown who printed it, but this file was in the root of C: and didnt contain any other backup files you would normally see) and then a corrupted backup (this is the one we pulled after firing the machine up a few months ago)

Restoring the original paper parameters did NOT go well. It ended up locking the NC card up to a point where I couldnt read or write to the memory. To fix this I had to disconnect the serial cables before booting the pc in order to restore a different backup.

Restoring either of the other 2 backup sets yielded no results.

Here are more details about the problem: Programs run fine until tool changes. When a tool change is called we get "T10 FIN WAIT 0001". Scrolling through another forum I found 2 users with the exact same problem here: http://www.*******.com/forums/mazak-mitsubishi-mazatrol/95520-software-forum.html

Also found manual here saying its waiting on rapid traverse deceleration so it appears the thread above is correct in their assumptions : http://dl.mitsubishielectric.com/dl/fa/document/manual/cnc/ib1500087/ib1500087a.pdf

We are currently monkeying around with checking switches and limits, but if anybody has any other ideas we are all ears.

Ok, we put a handful of hours into this thing this weekend and have some more info as well as made it worse.

Started ohming stuff going to the spindle, no issues. Issuing TXX to rotate the toolchanger works, but as soon as M06 is issued it goes to T10 FIN WAIT 0001. Havent gotten to ohming everything else in the spindle, but everything directly going to the spindle controller checks out. The i/o stuff is a lot more in depth and the schematics are helpful but very hard to read.

Previous to this weekend we have gone through restoring backups, comparing files, etc... We have 4 sets of backups.
set A is newest parameters with rigid tapping.
set B only has rigid tapping changed.
set C is corrupted and was the backup we pulled after the battery died
set D isnt really a set. It is an all.prm file that matches a paper copy we have that came with the machine, but is far from the file we have been running.

Set D is unusable. Set A and B have the same results (as expected.)

Yesterday we started running into some quirks where the backup utility would no longer function. We would click restore and it wouldnt do anything. Same with backups. Using file transfer we were able to pull files but not able to delete, upload, or rename files on the NC card.

After reading through a bunch of manuals and reading how to format and recover from a bad battery, we decided to do just that. After all, we went through this 6 months ago and it worked, so why not do it again?

Went through formatting the NC card via the device manager. Tried to restore and nothing happened like before. Tried to file transfer to overwrite some of the files like all.prm and other files but received errors saying it was unable to.

Starting up meldasmonitor its in japanese now, (which I have no idea how to set that back to english even though that program is garbage) and the gui meldas obviously sees the card with no parameters. Unable to file transfer with that program also.

So do we have a hardware error? Does anybody know the procedure to recover from this because I think we have the wrong instructions. (and cant remember what we did last time).

We will be calling meau tomorrow but Id like all the help I could get.

Ok, so we got out of the woods of japanese text. It took a dozen reboots and attempts to get file transfer to work I was able to get all.prm back into it and then the rest of the stuff. Backup/restore still doesnt work.

Id bang my head against it but I think this unit is harder than my skull.

Going to attempt to see what I can do with the ladder. (if I can even get the utility to open it.)

You shouldn't have a battery backup, there is a capacitor that is used to power the memory. I looked I do not have a set of parameters. I got rid of my VMC-950 last year. By the way that is not a 12,000lb of iron, but a 16,000lb of iron. Mitsubishi makes a retrofit for your machine, around $9K. The biggest problem is the relay board and other boards in the cabinet are Mighty and not all of them are still available. There is a machine that is running out in SoCal that you could buy and use the control from it. I really liked my machine, but it got to the point where is was unreliable. Parts where a nightmare to get from Mighty.

Had to look it up..

MIGHTY VIPER V95 CNC VMC FOR SALE - YouTube

hmm, whats 2 tons these days? Good thing nobody is counting because I remember 12k on the freight invoice.

As for the battery, Are you sure? Mine has the HR621B card which does have a battery holder, see mitsu document bnp-b2191. Also when removing that battery there was definitely juice still in 2 capacitors. Ended up waiting until card was void of all life before reinstalling (caps under 0.1v) and attempting format/restore processes.

I have been unable to format the card because the instructions for meldasmagic monitor doesnt say how. It says to go into setup and the steps after that, but not how to get there.

So there is actually a VMC950 for sale maybe 10 miles from me right now in Largo FL, but we were going to call Meau first before trying to get some random machinist from letting me poke around his machine. The machine is likely not powered, but I would just need power to the computer right?

As for that mitsubishi retrofit, Is that the one that goes to the M65S controls? I havent been able to find any information about it other than the press release in 2013. Say we werent able to fix the current controls and retrofit was the only option, would this be a viable option to keep the cost down because I wouldnt be purchasing a new set of drivers?

Another weekend of tinkering with the mill so Ill recap so some of the information is updated.

Going through the parameters and changing some, testing, reverting, the whole problem is the spindle wont orientate. M19 produces the same error which going to the manual is: Waiting for spindle orientation to complete.

Parameters say to use the PLG to set orientation and that the encoder was a valid input, so I changed it to use encoder for orientation by changing sp037 from 0004 to 0001 but that didnt work. Goes into emg alarm so theres probably some supporting parameters not set.

So now that I know its PLG, how would I test this or what other parameters would I be looking at? If its PLG I wouldnt have any magnetic pickup on the spindle right? When M19 is issued it doesnt even try to spin so something before reading the PLG for orientation must have an issue.

Does the encoder work, all channels?

MJPfin said:

Does the encoder work, all channels?

Click to expand...

What do you mean? I don't know how to test it. I also haven't been able to find a servo diagram, only calibration, specs, and parameter manuals. It's a sj-pf-11 servo and I assume built in encoder because this is the model with the fan on top. No gearbox. Encoder connection from the amp goes to the same j-box on the spindle.

We do have a scope if that's involved with testing.

You need wiring diagram or encoder pinout.
A+ A- B+ B- Z+ Z- and encoder Vcc and ground pins. If it is a incremental quadrature encoder.
You should see squarewave pulse on each chanel, difrential signal between poles and 90deg separation between A and B chanel. Z chanel is indexing pulse once per revolution of the encoder.

Marko

MJPfin said:

You need wiring diagram or encoder pinout.
A+ A- B+ B- Z+ Z- and encoder Vcc and ground pins. If it is a incremental quadrature encoder.
You should see squarewave pulse on each chanel, difrential signal between poles and 90deg separation between A and B chanel. Z chanel is indexing pulse once per revolution of the encoder.

Marko

Click to expand...

Thanks Marko, Ill give that a shot and see what it looks like on the scope.

The pinout has A B and Z + & -, +5v, Ground, +24v, and MOH. When Im not on the road ill look into what those last 2 are for as I cant remember. (I keep wanting to say music on hold but thats the IT guy in me.)

Just a quick update. I was able to scope the encoder after a crash course in scopes. I originally thought there was way too much noise on the line but after talking to MEAU the tech said that he normally has to run the filter down to 10-15kHz, which i was running at 20-25kHz filter which ended up looking ok. Trigger off the Z and confirmed A and B were 90 deg off.

After telling MEAU what was up they recommended amplifier replacement. This would be the second amp in 3 years. At least we have a no restocking fee return policy because the technician said it was the recommended fix.

We viewed the PLC memory and the bit for orient isnt being set, which if I understand correctly that means the amplifier is either A) not getting the signal to orient or B) isnt sending the signal back that it completed an orientation. I think it is the latter because the technician wouldnt have recommended an amplifier if he thought the amplifier was receiving the signal to orient. This is also supported by the fin wait 0001 which is "Waiting for MSTB completion", aka waiting on that bit to be set.

Hi, Do you still have this machine?
I have several param files and have one of these machines with the spindle not turning on except in a tool change.
Thx, Bob

rdgroup said:

Hi, Do you still have this machine?
I have several param files and have one of these machines with the spindle not turning on except in a tool change.
Thx, Bob

Click to expand...

Yep, ended up moving it to my home garage but haven't put it back together to continue troubleshooting. Work and other higher paying hobbies have been in the way.

How similar of a unit do you have, and it sounds like you have the exact opposite problem I have.

Hi,

Did someone here have a Viper VMC-950 who is still running? The hard disc on mine juste got issue on boot sequence (dll problem). If someone can have a copy of the hard disc I can paid for this.

Thanks

JulienCote said:

Hi,

Did someone here have a Viper VMC-950 who is still running? The hard disc on mine juste got issue on boot sequence (dll problem). If someone can have a copy of the hard disc I can paid for this.

Thanks

Click to expand...

That makes 2 of us. Getting a visual basic error "run time error 5, invalid procedure call or argument."

That is also what I got on the old hard drive in 2011 and got the CF card replacement. Had a copy of it but lost the copy in a computer crash without realizing it. Now Viper says I have to do the upgrade for at least $6500 or is it $9500.

Anubody have the install disks or a viper that is running? It took me only minutes to copy my CF card once I bought the reader. I will buy someone a reader and CF card pay for time if I can get someone to make me a copy.

Or Julien. if you are still having problems maybe we can combine the systems and get a complete system out of it!