Terminator 8 channel losing 7 channels

Hi guys,
Just flew back to Dutch and got on the boat.
Went over a problem they have been having with my relief before he left and have poked at it for a couple hours now but kind of scratching my head with this one. Never seen it happen before and I am still learning to get around in this AD stuff.
Hoping someone has experienced this before and could give some input.

We have a TIF-08DAx analog output module located in slot 5 of a terminator rack. 7 of the 8 channels 2-8 will just die (go to 0v output) after about 5 minutes. Channel 1 will continue to work as normal.
You can cycle the main Do-More processor (in another location) and the terminator analog module will work again for about 5 min and then channels 2-8 will just die again.

So far what I have tried is to disconnect all outputs from the module. (get same results)
Replace the module and base. (get same results)
Replaced the base on the other 4 modules in slots 1-4 thinking it might be a back plane problem. (same results)

I am a bit stump here and what I find even more confusing is that the program data table does not show I have 0 volt output on the channels, it shows the same as my set point but when you test with a meter there is 0 volts on the outputs.

(I miss using Allen Bradley)

Under a time crunch before we leave the dock so just thought I would throw this out there quick to see if anyone who is familiar with AD might have some input.
Off to poke at this with a sharp stick again but will check back in a while to see if anyone takes a bite at this.

Thanks,
BCS

A thought . . .

On the PAC that I work on, I need to match the power supply capacity when using numbers of AOs. On that device, analog output cards typically use a 'large' amount of backplane current. There are other AO cards that are 'loop powered' which use an external DC power supply.

Could the combined output of a number of analog outputs exceed the rack's power supply capacity and it over heats and drops channels?

Has it always worked before?
What else is in the rack?
If it did work what has changed?

danw said:

A thought . . .

On the PAC that I work on, I need to match the power supply capacity when using numbers of AOs. On that device, analog output cards typically use a 'large' amount of backplane current. There are other AO cards that are 'loop powered' which use an external DC power supply.

Could the combined output of a number of analog outputs exceed the rack's power supply capacity and it over heats and drops channels?

Click to expand...

That is what I am thinking too

I'd be thinking similar to the above as well. In AB world there is also a power supply distance rating for each module, in terms of how many cards you can place between it and the power supply - some specialty modules have to be closer to the power supply than say a digital input card. No idea if the same applies with AD, though.

Answers to the three questions in post #3 will help narrow things down somewhat.

Hi guys, thanks for the responses.
I thought of this also but it seems that this analog output card is powered from an external power supply and not by the back plane.
The other modules preceding the AOM are from right to left:
16 point RTD module
16 point digital output module
16 point digital input module
16 point digital input module
controller
power supply (through back plane)

Yes this all worked and has for years.
I just got here after a month off so kind of stepping into the middle of this.
My relief said it stopped working when they started up for the season about a week ago. He said he has been tracking down bad cables and such during production but had to lock the stepper motors down and pull the fuses in order for them to run the plate freezers in manual so they could produce last trip.
Today is the first day he was able to start really trouble shooting this. (we are offloading now) He had to go catch his plane off this rock so now I am starting from square 1 to figure it out.
Never had a problem like this with Allen Bradley, (configure card and run) but I am still new to this AD stuff. Seems like it would be all the same but unfortunately it does not seem to be working that way.

Thanks again for the replies and if you have any other ideas shoot them my way.
I am looking up these modules on internet and backing my way through it to see if I can get it going but still don't understand how 7 out of 8 channels die but 1 will keep working.....yet.

I have never worked with the AD stuff, but if it were me, I would be looking at the other stuff connected in that rack. Sounds like something is drawing down the power. First thing I would do is pull the other cards and see if you keep power on the analog. If you do plug the others in one at a time then wait 10-15 min to see what happens. If that doesn't do it, and you haven't tried it yet, try disconnecting each channel on the analog one at a time and see if you can isolate it to one channel giving you issues.

Bubba.

I will give it a shot but like I said before the analog card is powered externally.
I have 24vdc where the card is powered, so it does not seem that there is a ground fault pulling down the external power supply.
Also 1 channel on the card continues to work......so does that make since?

Could not hurt to try at this point though, we are not running the plant at the moment so now is the time to give it a try.
I will let you know if something comes from it.

Thanks.

willxfmr said:

I have never worked with the AD stuff

Click to expand...

From what I have seen so far, I would say that is a good thing.
I am not all that impressed coming from an Allen Bradley world.
I have never seen so many I/O cards go bad.
Have seen more AD stuff changed out in 1 year that I did AB stuff in 10 years.

But this is what they got here so I just have to grin and bear it.

I missed your mention of the external power supply. I would still attack it the same way, but I might start with the analog channels first. Since you mentioned having to change cards a lot, you may not want to rule out a DOA card. It wouldn't be the first time a brand new part right off the shelf kept me from draining the worlds coffee supply.

Good luck.

willxfmr said:

I missed your mention of the external power supply. I would still attack it the same way, but I might start with the analog channels first. Since you mentioned having to change cards a lot, you may not want to rule out a DOA card. It wouldn't be the first time a brand new part right off the shelf kept me from draining the worlds coffee supply.

Good luck.

Click to expand...

LOL,
Yep already covered that one also,
disconnected all outputs and gave it a try,
changed output card twice just to be sure. (only have so many spares and its a long swim to the supply house)
Thanks for the replies though, I will take what I can get, somethings bound to shake the answer out of the tree.

I have not had to change this output card before today, but we have lots of AD PLC's and terminator RIO on here.
Don't get me wrong, this AD stuff does not go out all the time, but it goes out at a much greater rate than I ever seen with AB.

This one is a head scratchier for sure.

Had to grab some dinner but headed back down now to keep at it.

And you say it repeats the cycle with all loads off the card.
5 minutes good then 0V on 7 of the 8 channels.

Is there anyone way it is a programming issue. memory being overriden

Bering C Sparky said:

7 of the 8 channels 2-8 will just die (go to 0v output) after about 5 minutes. Channel 1 will continue to work as normal.
You can cycle the main Do-More processor (in another location) and the terminator analog module will work again for about 5 min and then channels 2-8 will just die again.

Click to expand...

It would be interesting to be able to clarify the 'about 5 minutes' part. Is it about five minutes or is it more like exactly 4:51 every time? I'm thinking of the possibility of a seemingly unrelated timer somewhere causing trouble.

labeledas said:

And you say it repeats the cycle with all loads off the card.
5 minutes good then 0V on 7 of the 8 channels.

Is there anyone way it is a programming issue. memory being overriden

Click to expand...

I have learned to never say never.....but I highly doubt it.
My relief was the one who originally wrote the program and he did not mention making any changes to the program.
Also I have the analog output values forced this entire time, so that would rule that out.

I just moved the analog module to slot 0 so it is first in line on the back plane, going to wait a while and see what happens.

Strange though, this has worked in the previous configuration for over 2 years.

Doug-P said:

It would be interesting to be able to clarify the 'about 5 minutes' part. Is it about five minutes or is it more like exactly 4:51 every time? I'm thinking of the possibility of a seemingly unrelated timer somewhere causing trouble.

Click to expand...

Just guessing at the 5 min part.
Have not timed it and it is very possible that sometimes its 3 min and sometimes its 5 min. Was not holding my meter on the output the entire time, just checking it every few minutes.

I have had the analog output values forced the entire time so that would also rule out any program anomalies.

Thanks for all the replies guys, it is nice to know others have you back when you are having problems.

If this were AB it would be a walk in the park, I just have to get comfortable with AD i guess to feel more confident in what I am doing with it.
Hard to mess with working systems when we are in production, but hopefully I will get some bench time to play with it this season.

I was signed up for the AD factory seminar in December in Georgia but they cancelled it at the last minute.

I just moved the AOM to slot 0 will go back down in 10 min and see if it likes that slot better.