Find M-Codes in PMC-L ladder dump?

I have a dump of my 0T-A (PMC-L) ladder and I'm trying to diagnose why my chuck clamp/unclamp (M51/M52) codes don't actually do anything. When issued, the control just waits indefinitely. No error, just pause, forever. This feature is listed as optional in my manual. I really like to get it working. Obviously if it is in the ladder then I need to sort the hardware to make it work. If it's missing from the ladder then I'd like to add it. Being this is first venture into ladder programming I'm struggling to gather enough information to understand what I'm looking at. Anyone have a PMC-L ladder manual?

I've attached my ladder. Maybe someone more experienced can find it in the ladder? I also attached a scan of the chuck schematic. It's hard to read but it's all I have.

Thanks!

If a M51 or M52 is issued, does either of the relays (outputs Y48.Y48.5) operate?
In some cases an issue of an M code requires a confirmation by way of a FIN(ish) signal back to the PLC input.
If the issue of an Mcode freezes, either the M code is not written or the FIN signal never comes back.
The ladder rungs should show if the outputs are activated.
Al.

Looking at the schematic output Y48.4 controls K113 and Y48.5 controls K114. During normal operation, using the foot pedals, K114 is active when the chuck is open, and K113 is active when it's closed. I didn't see any change in state when issuing the M51 or M52 commands from the MDI. I've also tried in Auto mode in the past.

I don't see any errors on the operator's panel suggesting the command is waiting for FIN state.

I assume this is the correct portion of the ladder? Is there a way to see if the NC is sending the F signal to the PMC when executing M51/M52.

Attachment 438666

You can see on the screen what functions are made in the ladder rung.
But the BMI, which is the bus that the NC and the ladder, PMC communicate with each other.
The Ladder sends a G value to the CNC and the CNC responds with a F code, an F value is also used to activate any ladder function.
Al.

Al, thanks for your help. I will do some more poking around on Monday.

I have been on a quest to sort this clamp/unclamp m-code issue for a long time. I copied my eproms and had a guy in India dump the ladder, but once I had the dump it made absolutely no sense. I have zero ladder logic experience. I was hoping the ladder would reveal some switch that was not set. I didn't realize how crypic the ladder logic was. I will figure it out... eventually. ;)

It looks like my M codes under SUB 4 as BCD. I have 0011, 0111, 0211, 3011, 0311, 0411, 0511, 0811, 0911, 1111, 1211, 7011, 7111, 7211, 7311, 7411, 7511. So, it's very clear M51/M52 are not in the decode list.

So I need to add a SUB 4 to decode 5111 and 5211 and then modify the Y48.4 & Y48.5 rungs.

At least it's starting to make sense.

Unfortunately it looks like you don't have the version of the OT that displays the ladder on screen with the status of the rungs etc.
Al.

Yeah the 0T-A is pretty limited. No ladder display.

I've been pouring over the schematic and the ladder. It's beginning to make sense. I sent the schematic off to Dalvi, who did the ladder dump, says he can add M51/M52 code and put it across X6.3 and X6.4 (chuck open/close) and it should work. To me it looks like he's set R6333.4 and R6333.5. I'll post up the proposed code changes once he gets back to me.

How is the chuck activated, Pneumatically?
Is it necessary to confirm the full open close function?
If so some kind of sense has to be implemented and the FIN signal input used.
Al.

Quote:

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Originally Posted by Al_The_Man

How is the chuck activated, Pneumatically?
Is it necessary to confirm the full open close function?

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The chuck is hydraulic. It has stoke end switches. This is the ladder for the foot switches. Couldn't the SUB 4 DEC 5111 simply activate the same registers? I'm pretty sure the stroke action on this lathe is all open or all closed on activation, I can't pause it mid stroke. The Y48.4/Y48.5 logic appears to check the end of stroke switches. Not sure how to send the FIN signal.

There normally is a whole rung in the ladder that takes care of all FIN (done) signals and sends a signal back to the CNC side via the G output function.
If you have stroke end switches then these normally would be added via spare inputs to the ladder.
Also the MTB would normally have a ladder listing with all the I/O and rung functions listed
Al.

Quote:

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Originally Posted by Al_The_Man

If you have stroke end switches then these normally would be added via spare inputs to the ladder.
Also the MTB would normally have a ladder listing with all the I/O and rung functions listed.

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Chuck limits are X6.1 front, X6.2 back, and X6.3 clamped. They are already in the ladder.

The MTB is SZIM (Szerszamgepipari Muvek), a state-owned company in Budapest, Hungary. It was closed in 1991 with the fall of communism. The lathes were imported into the US in the 80's as SimcoTurn. The model I have is a SimcoTurn HL-320. It is fairly popular/common in eastern block countries as the SZIM EEN-320, minus the Fanuc control. All I got with the machine was a generic Fanuc manual, and a notebook with some basic handwritten instructions. I managed to scrounge up schematics, an EEN-320 manual in Hungarian, DC drive manual in Russian (with German diagrams), and a handwritten list of parameters. Enough to get it up and running. Getting anything like a ladder list has been impossible. I ended up pulling the eproms to get the dump I have. I'm flying a bit blind but I'm determined to figure it out. ;)

Dalvi was kind enough to send me my ladder. I installed an old laptop with FreeDOS, enabled NANSI.SYS, and installed FLADDER. It was surprisingly easy to get running. It took a bit to figure out how to add/edit stuff, but it wasn't bad. I installed PRN2FILE to redirect the LPT1 port and hacked up the printer .INF file to remove all the Epson ESC/P codes. Once I had a clean dump of the ladder in a text file I had to transfer it. I installed UBS drivers so I could mount a thumb drive is DOS and copied it to my MacBook. Kinda of pain working on the old machines when you don't have and machines with floppy drives anymore.

I made two changes to the ladder. First I added two SUB 4 DEC sections for M51 and M52. Next I added some logic to the chuck control to accept the M codes. Not sure if I have this totally correct and I'm sure it could be inverted someplace. Could something like this work or am I missing something? R610.5 and R610.6 contains all the interlock logic like chuck limits and spindle stopped.

Attachment 438918
Attachment 438922

You are close. For the M Code to complete you have to trigger G120.3 in the ladder. Two conditions will have to be true in order to complete this or the M code will just hang. R607.2 & R607.3
R607.3 is fed by R607.1. This rung should have R609.3 & R609.4 followed by the confirmation inputs.
R607.2 will take care of it self so no need to worry about that.
F150.0 is the M Strobe signal. All that means is an M-Code is active. This will go low when the M Code is completed. M codes are completed when G120.3 goes high.

Hope this helps.

Quote:

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Originally Posted by drdos

You are close. For the M Code to complete you have to trigger G120.3 in the ladder. Two conditions will have to be true in order to complete this or the M code will just hang. R607.2 & R607.3
R607.3 is fed by R607.1. This rung should have R609.3 & R609.4 followed by the confirmation inputs.
R607.2 will take care of it self so no need to worry about that.
F150.0 is the M Strobe signal. All that means is an M-Code is active. This will go low when the M Code is completed. M codes are completed when G120.3 goes high.

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Thank you for the help! I added the R609.3 & R609.4 to R607.1. Does this look about right? I also uploaded an updated dump of the whole ladder.
Attachment 438964

This morning I tried the changes I've made so far. Good news is that the machine still booted up with the new eproms... bad news is that the chuck didn't work at all. No foot pedal control nor the new M-codes did anything. Clearly I still have something broken someplace.

Yesterday, I reached out to Yasuda of pmcladder.com for a quote on making the required ladder changes, because I've never done any ladder editing before. He was kind enough to look it over and said: "I think the modification of the ladder program that you have done so far is good. However, since there is a possibility that the M code will end up not being executed, I am attaching my proposed changes."

I have made the proposed changes and it compiles fine. Is fixing R607.1 FIN enough or do I still need to make other changes?

I've attached the proposes changes from Yasuda (huge thank you), my changes, and a ZIP of my ladder if anyone has a desire to look at it.

I would sincerely like to thank everyone who has helped me so far. I value your experience. With the high school closed I've had a lot of time to tinker. I've learned a LOT. I'm pretty excited that I may actually get this working. :)

I don't think it's related, but Dalvi mentioned there was a problem in NET 00344 when he originally discompiled the ladder. It appears to be fixed correctly. I'm stumped as to why the chuck didn't open or close this morning. Is this related in any way?

I would really like to nails this down before I ask Dalvi to remake the binaries.

I did some more testing this morning. I was mistaken yesterday that the pedal/m-codes didn't work at all. In more careful testing this morning I found that the chuck would respond to a single pedal input or m-code on startup. It ignored any subsequent inputs. For example, if the chuck is clamped on startup and I press the unclamp pedal it works, once. Likewise, if the chuck is clamped on startup and I issue M52 (unclamp) it works. It works both ways, clamp or unclamp, but only once on initial startup. I think I need to figure out why the second clamp signal is ignored.

I think the logic in N00253 and N00254 is the cause.

I rewrote N00253 and N00254. I'm not sure if I really changed anything other than simplifying it. Can anyone see something I should change?

The chuck is only working 1 time on machine start up.

Attachment 439208