[RichmondLabs]

Hey guys. First, I'm brand new here... so if I'm posting in the wrong part of the forum, please let me know now.

Getting to the point; I bought a nice used machining center about 25 years ago, but never actually got around to using it. I brought it in, set it up, hooked up the air and electricity, played around with it a little, but I didn't understand how to program it at the time. Then I got busy with other things (I'm sure you all know how that is), and it just ended up sitting there unused for years.

Anyway, now I have a couple of other (previously manual) machines here in the shop that I have subsequently converted to CNC control. Because of my experience with them, I know enough at this stage to operate the machining center, and I have work for it as well. However, although this machine worked fine when I bought it, now the control is totally dead and unresponsive. Well... almost totally... when I flip the toggle switches on, the corresponding pilot LED will light up... but that's the ONLY indication of life on the control itself.

I would add that when I turn on the main disconnect, the hydraulic pump comes on immediately, along with the automatic lubrication pump and a couple of fans. Note that I have no control over any of this activity either, other than turning the main disconnect on or off.

So finally my question: Are any of you knowledgeable enough to guide me through a troubleshooting session on this particular control? And if so, is anyone willing to volunteer the time?

Thanks,

Richmond

[Al_The_Man]

One thing with the 6 series, IIRC, is that the 3ph supply phase rotation has to be correct.

[RichmondLabs]

One thing with the 6 series, IIRC, is that the 3ph supply phase rotation has to be correct.

Hmm...
Well, nothing has been changed in that respect since it was installed (and working), but tomorrow I'll swap out a couple of lines anyway, and see if there is any change in it's behavior afterwards.

Thanks for your reply.

Richmond

[Al_The_Man]

If it worked previously then the phase problem should not be an issue.

[RichmondLabs]

Well I was mildly hopeful, but I tried swapping out two of the phases today, and it had no perceptible effect whatsoever.

Richmond

[memoryman]

Call me at 289 389 6117 9-5 EDT and I'll give you some time.

[Jim Dawson]

You have already built a couple of other CNC systems. Why not just replace the antique Fanuc system with modern hardware/software. It would most likely be less of a hassle than trying to get an old control up and running, as well as allowing you to run G code programs with modern cutting strategies.

[RichmondLabs]

Well I've considered that of course. But I like the look of this control (that's important to me...), and I think it would be adequate for the machines intended use.

Ultimately, it will depend on just how much trouble and expense I encounter getting this one back on it's feet. After all, retrofitting is not that easy either.

Thanks for your interest.


Richmond

[Al_The_Man]

If that has the Fanuc DC motors on them and the brushes have not been checked for a while, it may be worth a look.
I have some I am getting rid of now that I am retired.
The manual gives the min length IIRC.

[RichmondLabs]

If that has the Fanuc DC motors on them and the brushes have not been checked for a while, it may be worth a look.
I have some I am getting rid of now that I am retired.
The manual gives the min length IIRC.

Thanks. I'll keep that in mind if I can ever get it going again.


Richmond

[RichmondLabs]

I think I have this problem narrowed down to the IO board. Anyone know why it might have a short in the 24v part of it's circuits?

[Al_The_Man]

I think I have this problem narrowed down to the IO board. Anyone know why it might have a short in the 24v part of it's circuits?

Generally the I/O boards use opto isolation and the 24vdc is for the external circuit connected to the opto input on the board.
Do you have any manuals for the M/C?

[RichmondLabs]

Generally the I/O boards use opto isolation and the 24vdc is for the external circuit connected to the opto input on the board.
Do you have any manuals for the M/C?

Bill was nice enough to provide me with a maintenance manual that is very close to mine, and the wiring schematics as well, although the schematics are hard for me to make sense of.

With the help of those, and a lot of trial and error, I've been able to determine that there is definitely a short on the IO board's 24v circuit. I read though every similar post I could find on this forum, and I found that other people have experienced the exact same problem, although no one has posted a solution for it as yet.

I disconnected that one feed from the power supply board, and now my monitor comes on, the motherboard has power etc... But the monitor display is skewed to the point of being unreadable. So that is another issue that will need to be addressed.


Richmond

[RichmondLabs]

...looking for a short or just no 24V flowing to Engage the EStop string?

It's a short on the IO board.

Richmond

[Kevin Taylor]

It's a short on the IO board.

Richmond

I have a machine with a 3T control that is as I understand it is a striped down 6 and it has D size battery's for parameter back up could that be the problem? Mine has been sitting for a while and I hope I haven't lost the parameter's but I do have the list. I will follow this

[RichmondLabs]

I have a machine with a 3T control that is as I understand it is a striped down 6 and it has D size battery's for parameter back up could that be the problem? Mine has been sitting for a while and I hope I haven't lost the parameter's but I do have the list. I will follow this

It's a dead short. Haven't had a chance to trace it down yet. I was hoping someone here might had had the same issue, and would be able to point me in the right direction, but it looks like I'm on my own. I'll know what it is within a couple of weeks.