RSLinx OEM comm problem

I have a comm problem that I thought I would shoot over here before I start reinstalling stuff. I administer a SCADA system using AB PLC5s, CompactLogix, AB vfds, and AB power monitors. All AB stuff. SCADA is Proficy iFix. Here is the issue - I have one PLC 5/80E that has stopped responding to the RSLINX OEM app on my development computer. It will talk to other SCADA boxes on the network and is servicing the iFix HMIs just fine. All other devices are responding. I can ping it from my development box. I can bring up the web page for it with my development box. It just stopped talking to RSLinx. This has been communication for years. I am thinking i need to re-install RSLinx on my development box. I have not done any updates at all. Anyone have this happen to them?

I would try deleting the RSLinx Topic servicing the PLC5 and then re-add it back on, making sure the name of the topic is identical to the original one and obviously "pointing" to the right CPU; I remember having to do it several times over the years, especialy with PLC5 processors.
What type of networking are you using between the Linx machine and the PLC5?

I already tried deleting the topic. All communications is Ethernet. So odd that I RSLinx can talk to all processors but not that one. And the SCADA servers can see the PLC just fine in their RSLinx.

I am doing a reinstall of RSLinx right now.

reinstall of rslinx had no effect. hmm

Have you tried deleting the topic, deleting the Harmony project then re-creating the OPC Topic?
http://literature.rockwellautomation.com/idc/groups/literature/documents/gr/linx-gr001_-en-e.pdf
https://rockwellautomation.custhelp.com/app/answers/detail/a_id/48241

Attached is what I see in RSLinx. .93, .94, and .95 are identical PLCs in a cabinet.
This morning, I set enabled RSLinx ethernet on a laptop and connected to the PLC network and .95 didn't show up.

I am starting to wonder if I should toggle power to the PLC, but it is controlling 24/7. I would hate to toggle it and then have all the scada communication go down to the HMIs

Do you have any other means to connect to the 192.168.2.95 Ethernet PLC5?
Are you running RSLogix 5?
All Ethernet Enhanced PLC5 controllers provide a Serial RS232 port (Channel 0) over a 25-Pin D-shell connector.
Also, the PLC5 on-board Channel 1A provides DH+ communications provisions.
If cycling the power to the controller is not an option,you will have to use one of the two above mentioned protocols/means, connect RSLogix 5 Online to the CPU and verify the Channel 2 (Ethernet) functionality eventually resetting the Ethernet communications port.
Chapter 11 of
http://literature.rockwellautomation.com/idc/groups/literature/documents/um/1785-um012_-en-p.pdf

dmargineau said:

Do you have any other means to connect to the 192.168.2.95 Ethernet PLC5?
Are you running RSLogix 5?
All Ethernet Enhanced PLC5 controllers provide a Serial RS232 port (Channel 0) over a 25-Pin D-shell connector.
Also, the PLC5 on-board Channel 1A provides DH+ communications provisions.
If cycling the power to the controller is not an option,you will have to use one of the two above mentioned protocols/means, connect RSLogix 5 Online to the CPU and verify the Channel 2 (Ethernet) functionality eventually resetting the Ethernet communications port.
Chapter 11 of
http://literature.rockwellautomation.com/idc/groups/literature/documents/um/1785-um012_-en-p.pdf

Click to expand...

I currently have a laptop connected to the plc5 via DH+
I set up the laptop to communicate via ethernet and plc5 would not communicate with the laptop. It could see all other ethernet PLCs on the network. This was a test of a "new" connection. I have since disabled the ethernet driver on the laptop and am communicating via DH+

The IP configuration is correct (confirmed over DH+), it has not changed from when it was setup several years ago

Other SCADA HMIs are communicating with this PLC via RSLinx. I rebooted my computer last monday, and that is when the issue with my PC started.

Embedded web server in plc responds to browser.

PLC responds to ping

The way it is acting, is that it will not communicate with any "new" connection attempts, as rebooting my computer stopped the connection and tried to re-establish it upon booting, and a new connection with my laptop could not communicate. I have no spare for this processor, and am reluctant to reboot the processor or any of my HMI computers for fear of taking the whole system down. I may just have to do this in order to find the problem.

since nothing has changed,
could be that you have an identical ip address somewhere else in the plant.

regards,
james

The issue is RSLinx on your laptop - the other RSLinx installations on the HMI's are functioning (as stated).

Delete the harmony files on your laptop and RSLinx will rebuild.

The issue started before I connected my laptop to the plc. I wanted to connect via DH+ to see if the plc had any errors or flags.

Maybe the issue resides on my Development computer. I will look into deleting the harmony files on that.

so just delete harmony.hrc and harmony.rsh and restart?

just deleted harmony files, reboot, restart RSLinx, all plcs on my network show up EXCEPT the problem child. I think I just need to toggle power on this and roll with the punches if it stops talking to my SCADA nodes on power up.