Intermittent comm loss to 5/05 and Rslinx

[rguimond]

I tried a different cable today with the same results. There is another plc in the same building that is sharing the same switch, i can plug my laptop into the switch ping the other 5/05 and get no errors. Then ping the problem plc and get 20 some errors.

If you have another SLC 5/05, try swapping the power supplies. It only takes a few minutes. I spent weeks of sleepless nights trying to troubleshoot a similar communications issue - turned out to be faulty (noisy) power supply.

 

[cirtcele]

I'll try the power supply swap this week i also spoke with an AB tech using our techconnect account his only suggestion was to save a current backup and clear the memory and short the cap after removing the battery then reloading the program. It was friday afternoon and i thought i'd wait until Monday to try that. Okiepc touched on an issue of some messaging edits that put it over the limit and caused some new connections i'm hoping he will provide some more details on this.

 

[n_lev]

Creation of new data files must be done offline for SLC controllers.

For the sake of argument, I'm pretty sure you can actually create new data file in SLC, but you can't modify the size of already existing file.
I'm not sure you can create Ethernet diag data file online though since software does it itself

 

[Culan]

I had a similar problem once. I had one ControlLogix supervising the line that consisted of 5 FlexLogix plc's.
One of the FlexLogix's would loose ethernet connection once every four weeks or so. It had a couple of ethernet powerflex's connected to it and i tried alot of diffrent changes to the settings to the powerflexes.

The problem finally turned out to be in another plc. The FlexLogix before (in line layout) had some consumed tags in the plc that had the problem. I finally found out that the rpi of that tag was really low, resulting in the producing plc faulted because it couldn't deliver fast enough.

This might not be the problem here but it's good to know when troubleshooting these kinds of issues.

Your plc, is it only talking to the scada system or is there any other plc's connected to it in some way?

 

[naag_slet]

Hello Certcele,
This is nagaraj from india(Bangalore).
Finally i hope problem with the SLC 5/5 communication card,anyway please try to reset the processocer by shorting VBB and GND on the PCB for few seconds(before shorting i request you to remove the battery plug)
Note:before doing this think wether you have the latest backup?and in the main routine of programme you have to remove the rung which is defined to load the memory from EEPROM at every powerup or memory currupt.

and after again you have to load the orginal backup and have a look into the problem again

Please find the attached photos to reset the SLC memory.
Best of luck.......
let me know the result to
[email protected].

Thanks
Naag.

 

[naag_slet]

Hello Certcele,
This is nagaraj from india(Bangalore).
Finally i hope problem with the SLC 5/5 communication card,anyway please try to reset the processocer by shorting VBB and GND on the PCB for few seconds(before shorting i request you to remove the battery plug)
Note:before doing this think wether you have the latest backup?and in the main routine of programme you have to remove the rung which is defined to load the memory from EEPROM at every powerup or memory currupt.

and after again you have to load the orginal backup and have a look into the problem again

Please find the attached photos to reset the SLC memory.
Best of luck.......
let me know the result to
[email protected].

Thanks
Naag.

 

[Ken Roach]

naag_slet, I don't wish to second-guess you without reason, but I have to ask why you are recommending a reset to defaults of the controller ?

From the symptoms and troubleshooting steps I have read in the thread, this is clearly an Ethernet port hardware problem or an installation-related problem affecting all ports of the controller.

How does that lead you to recommending a reset to defaults ? I want to understand your thought process on this.

 

[PLCMentor]

Ken,
I think what he is suggesting is similar to what the Rockwell tech suggested. I guess I wouldnt really have a problem trying this before replacing the processor or power supply. I would not think it would work, but I guess I would try it before ditching the old one.

Naag, I do think that instead of putting your email address the conversation should remain on the forum.

 

[naag_slet]

Hi to All,
Actually there is a chance to get CIP to freez,as i faced the same problem wih 1734-AENT and finally we fixed the problem by resetting the module.
So i hope there is a chance to to get solve the problem by resetting the entire module..
Thanks in advance for your understanding..
Naag.

 

[cirtcele]

I did not get a chance to try the suggested fixes today, i'm the only electrician at this wastewater plant and i must address other issues. I will post the results as soon as i get time to do so more troubleshooting on this problem.

 

[cirtcele]

I decided to replace the problem 5/05 with a new spare instead of clearing the memory and reloading the program in the existing 5/05. After replacing the 5/05 i pinged it 100 times and had no errors so it appears the problem is solved. I'll test the problem 5/05 in a rack i have setup on my workbench.

 

[naag_slet]

Nice,
Please follow my suggetion, i hope >95% we can fix the problem by resetting the memory of SLC5/05.

This is only happens in the CIP communication..

As we are all aware that some time restarting a PC could FIX the perticular ERROR and hang's...Nobody knows exact problem, its a thumb role.....

Thanks for your understanding,
Naag.

 

[cirtcele]

Today i took the time to try what Naag suggested, granted that it was in my test rack but after clearing the memory in the problem 5/05 and reloading the program the lost pings disappeared. I can't put the processor in run and check the comm because i don't have all the modules in this rack and it would fault as soon as i enter run. But it looks like this may have corrected the problem. I'm pretty bust today but i will make an effort to put this 5/05 back in service and let everyone know the results. Thanks to everyone for the input, i'm one of those electrical maintenence people who is required to repair anything and everything and sometimes i need a helping hand.

 

[OkiePC]

. . . I can't put the processor in run and check the comm because i don't have all the modules in this rack and it would fault as soon as i enter run. . .

You can inhibit the slots for which you are missing the cards, but then you may not be able to simulate the communications that are going on with the "real" machine, so it may not prove anything.

You can get around the I/O config mismatch by going to procecssor status, I/O tab, and then put a zero in the slots that don't match the I/O config. You can't fake out a rack size mismatch though. I've done this so I could test logic that uses PID which cannot be emulated by RSLogix Emulate 500.

Paul

 

[Ken Roach]

I am amazed that defaulting the memory and reloading the controller appeared to fix the problem. Floored, actually. It would have been my very last recommendation.

This is consistent with there having been a change to a setting (in particular the Duplex setting on the Ethernet port) after the program had been loaded on the original controller. Such a change would not show up in the offline program.

It is also consistent with any number of hypotheses about "CIP hanging" or accumulation of pixie dust in the controller's tube manifolds.

So I'm just going to say "good job on that" and move on.