RSLinx Classic no longer finds nodes [Help]

[vidp]

Hello all,

Some time ago we replaced a client's old Rockwell SCADA with Omron's SCADA. It was our first and so far only time working with Omron or Rockwell.

We used RSLinx Classic lite and 1747-UIC USB to DH485 adapter and then Kepware as an OPC server for Omron's SCADA.

The PLC's used are Allen Bradley SLC 5/03. In RsLinx Classic Lite I configured the driver as "DH485 UIC devices", selected the correct COM port and RSWho found the available nodes.

It worked fine for about 9 months then suddenly nodes couldn't be found anymore and the communication to the SCADA went dead. First I thought it might be the adapter cable so I replaced it but it didn't work. I tried installing a newer version of RSLinx but no luck. Then I came across something that said that deleting harmony files might help in situations like this. That didn't help either.

In the meantime the client has plugged in the computer containing the old SCADA which still works fine so the PLC's must be working fine.

I've run out of ideas what else to try.

If any of you have any experiences with similar problems I would greatly appreciate any advice.

Kind regards
Vid

 

[geniusintraining]

Hello Vid and welcome

First thing I would try is to manually configure the UIC using a different driver and change your COM port number, see attached for the manual config

 

[Ron Beaufort]

welcome to the forum ...

first I'd try the suggestion from geniusintraining ... if that doesn't work, then here are some questions for you ... note that this approach is intended as something to grasp at in case your efforts with RSLinx don't work out ...

what operating system is running on your computer? (Windows 10, etc.) ...

has Microsoft "pushed out" any updates to your computer lately? ... sometimes this is scheduled to happen automatically during the dark of night – and you might not be aware that it has even happened ...

do you have an IT department involved with the maintenance and security of this computer? ... sometimes these guys make well-intentioned changes to "protect" the computer system without realizing that they're making a mess of things that are important ...

has anyone added any programs or applications to your computer lately? ... sometimes the registry gets messed up when that happens ...

does your computer have a series of saved "System Restore" type files? ... if so, you might want to try going "back a step" or two and see if the problem goes away ...

good luck with it – and remember, the more we know about your problem, the more detailed help we can provide ...

 

[vidp]

Thank you both for your replies.

I've already tried configuring different drivers and com ports before and I've tried again but it hasn't worked.

The PC they use runs on Windows 10. I'm not aware of any recent updates but I looked in System restore if there are any previous versions saved. Sadly none dated back to before it stopped working.

Their IT staff has now made the user "administrator" as they didn't have all the rights on this PC before that.

I don't think any programs or apps have been added recently.

I've spent the day uninstalling Rockwell software, then I deleted files from the registry editor containing Rockwell and then I did a fresh install of the RSLinx Classic Lite.

There are still no nodes showing in RSWho.

I did notice one thing. I watched a YT video showing how to delete harmony files ( https://www.youtube.com/watch?v=ehcek7zRGg0&ab_channel=TimWilborne ) and then I noticed I only have one harmony file in my folder (Harmony.rsh). The other one (Harmony.hrc) seems to be missing. I don't know why that is but could this be part of the problem?


Best regards,
Vid

 

[geniusintraining]

Couple questions

What position is the switch in on the UIC?
When you open RSLinx and you are looking at the driver screen is there any errors? or does it say running?

EDIT: this is the video I made and it may help ( Allen Bradley 64 and 32 Bit PC 1747-UIC http://www.youtube.com/watch?v=uWgu1jdAPkE )

 

[vidp]

I've checked with the operator and the dip switch was in the 485 position. He changed it to 232 and it started working in seconds. It didn't even cross my mind to check the dip switch.

Thank you very much for your help!

Best regards
Vid

 

[geniusintraining]

Its the tough ones we overlook from time to time

Glad you got it work! :site:

 

[Ron Beaufort]

thank you for letting us know how this turned out ...

stay safe ... stay well ...