defcon.klaxon
Lifetime Supporting Member
Hey guys,
I'm working on an existing system that you may remember me mentioning earlier this week. SLC 5/05 at a wastewater plant. In addition to the master SLC, there's another Allen Bradley PLC in a control panel at a package filter. Basically this second PLC controls the package filter in a remote control panel and then provides status data back to the HMI which is RSView32.
Client called today and was asking if I could help troubleshoot an issue where the remote PLC is apparently not providing any info to the HMI. Here's what I've found so far:
1. PLC responds to ping
2. PLC shows up in RSLinx
3. I haven't made any changes to the system that would seem to affect this PLC
I've taken a look at the Nodes in RSView32, and find that the master PLC is set up to be read via Direct Driver. Really simple, it's just IP address as you'd expect. However, the remote PLC is set up as an OPC Server (In-Process). I've never tangled with OPC Server, and don't know the first thing about it or how to troubleshoot it. I'm going to do my due diligence with forum and Google searches but because I'm not unfamiliar with it, I was wondering if anyone could provide some info on what OPC Server is vs Direct Driver, and if there are any pointers on how to troubleshoot. Plant's an hour away so I'm trying to do as much remotely via TeamViewer before making a trip up.
Thanks for any help!
I'm working on an existing system that you may remember me mentioning earlier this week. SLC 5/05 at a wastewater plant. In addition to the master SLC, there's another Allen Bradley PLC in a control panel at a package filter. Basically this second PLC controls the package filter in a remote control panel and then provides status data back to the HMI which is RSView32.
Client called today and was asking if I could help troubleshoot an issue where the remote PLC is apparently not providing any info to the HMI. Here's what I've found so far:
1. PLC responds to ping
2. PLC shows up in RSLinx
3. I haven't made any changes to the system that would seem to affect this PLC
I've taken a look at the Nodes in RSView32, and find that the master PLC is set up to be read via Direct Driver. Really simple, it's just IP address as you'd expect. However, the remote PLC is set up as an OPC Server (In-Process). I've never tangled with OPC Server, and don't know the first thing about it or how to troubleshoot it. I'm going to do my due diligence with forum and Google searches but because I'm not unfamiliar with it, I was wondering if anyone could provide some info on what OPC Server is vs Direct Driver, and if there are any pointers on how to troubleshoot. Plant's an hour away so I'm trying to do as much remotely via TeamViewer before making a trip up.
Thanks for any help!
