The beacons are lit! Gondor calls for aid!!
I'm nearly about ready to admit defeat. OR at least that buying this machine was a mistake.
For the past couple years off and on I've been trying to work with a 1983 Traub TND360 that I believe was actually upgraded with a 1985/6 control. I bought it with the hopes that I could work it into production and start my own business venture from the ground up. In fact, my employer has been kind enough to let me store/work on it in the shop I run with the agreement that if/when I get it going I can use it to provide parts/service on equipment here.
The good news is I've been able to get it from a DOA state, to being ready to turn the drives on. I've needed a few new push buttons, a varistor replaced on the main power supply, a replacement operator panel, a new LED screen retrofit, a replacement servo drive power supply, a new timing belt on the x axis, and a couple broken wire repairs.
Even with all that, plus scooping up NOS cards off ebay, I'm still not into it as much as I'd have been for an operating machine.
The bad news is now I'm really hitting my head against the wall and am not finding any help anywhere. I think my contact at Index reached his patience limit because he finally just went through and sent me "everything [he] has about the TX-8". Mitsubishi's level of assistance was to recommend that I go onto their knowledge base at MEAU.com and register so I can find the manuals...that I had been working from for the past 6 months -_-
IF the TRA30/60 servo drives are in velocity loop I can dial in the velocity loop gain (VR1) and VR7 to the point where there's no motor rotation, verified by eye AND the resolver count on the control readout.
In position loop though, VR2 "has been adjusted at the factory. Do not touch this setting." -_- thanks Meldas, big help. Other settings are very obvious to not have changed as they have some resin still on the pot. Anyway as soon as I turn the drives on the motors are powered to what appears to be rapid speed and the control immediately faults out with error# 022 or 023 (whichever comes first). This is of course, a droop error, that if my german is worth anything equates to excessive following error caused by either a mechanical jam, a drive fault, a motor fault, or a control fault. Again, big help in the manual.. IF the motor leads are not connected to the drives everything is fine (DUH). I did manage to find a really kickin deal on a TRA31 drive, so I tried that out and the only result there is now I can't lockout the position loop to setup the speed loop -_- That, plus again this being on BOTH axes, causes me to believe the drives are probably fine enough that they are not causing this particular problem.
I can upload the pages from the manuals I'm working from when I get back to work on Monday, but for now I was just hoping if someone could verify or correct my logic going forward.
In the TRA30/60 & TRA31/41/61 maintenance manuals there is direction on which check pins are for what signals. They even provide neat little diagrams of the desired waveforms, but with little exception though they fail to say exactly what the signal voltage/amplitude should be and for what duration. I'm sure the techs from the 80's could just know, but I wasn't even born then so there's so many things that this "could" be that I'm really unsure as to whether I'm picking up a good signal, or a weak signal, or a plain old junk signal.
I think it's pretty obvious that the motors themselves are okay, because they can work in either direction at any speed when operated under pure velocity loop. Of course the shortfall here is there's no stopping it from running the carriages right off the ballscrews.
In the Mitsubishi L1/M0 manuals which very clearly operates under similar control principles there's even a guide on how to adjust the drive amps. Unfortunately they seem to rely on the machine being operational because the procedure specifies setting a certain jog rate for the appropriate axis...something I wish I could do at the moment.
I'm very nervous the control card itself is bad, but I suppose it's not impossible for both pickup units to be faulty?
So I put my scope on the test pins and believe I found some signals, but again I'm not comfortable enough to say any of them are "okay" or even if I'm 100% confident in my o-scope skills.
I was able to find a 4.7/8/9 V signal off of TCP1 for both drives, the velocity input to the drive from the NC. good?
The resolver excitation circuitry is there on both sin/cos waves for both axes (doesn't look like a sin or cos wave, but more like a sloped square wave @ 2.5ish Vpk-pk, and I see a resolver output that's a definite wave signal at around 1.5Vpk-pk.
What's throwing me is the tacho feedback signal. The books say the Sanyo RST series is supposed to send 2V per 1000 rpm. Who knows what max rpm is though? There doesn't seem to be ANY technical info purely about these tachs that's survived. In any case, my scope's automatic signal finder comes back with so much noise on TCP2 that I don't know what's a legitimate signal and what's not. If I raise the trigger up past 1.75V I do end up getting a 2V +/- 200mV stable signal that looks like a dying wave form and what causes me to question the tach's is that this is whether or not the motors are spinning. But how can a tach that's not spinning generate voltage?
The triangulation wave form is okay.
Continuity along the cabling for the tach's is okay.
Continuity for the cabling between ZP1 on the drives and the CNAx/J4 connections on the control are all okay.
Parameters are freshly loaded from the tape reader and all of that appears to be okay.
At its core is something is telling the motors to rotate very fast right away, but the control is able to both see that and say hey no that's wrong, fault out the error code, and shut down the drives.
I'm to the point where I'd be willing to hire an expert, as long as I could trust they knew what they were doing, because so far I've been able to reverse engineer farther than any of the tech help can at both Index & Traub. I'd also need to have funds to be able to do that though...so here we are.
Bonus prize is that whoever can help with this also might like to help me learn how to megohm a motor so I can verify the spindle motor is still good
In all seriousness though, I've put a lot of time an effort into this and I'd like to give it my best shot before I part it out/scrap or consider retrofitting a newer control so whoever can help, I'd very much appreciate it. This entire venture may be relying on whoever you are.
Help me Obiwan Kenobi, you're our only hope!