ControlLogix

Our plant is going to be automating quite a few fairly simple processes, in a distributed fashion. We are looking at using the ControlLogix, Ethernet/IP and FlexLogix. What are things to be mindful of? I'm curious as to the opinions of other users, rather then our local rep's opinion.

I am not a big fan of ControlLogix.

I prefer stuph that is simpler to teach the maintenance staff, and quite frankly, just plain cost effective (cheaper). And I am not a big fan of distributed I/O.

What you have described is okay, and should work quite well for you. It is a proven "system". Don't try substituting a different brand of drive.

regards.....casey

Don't forget to consider the compact-logix. Same instruction set but it uses 1769 IO, and it is suitable for low IO count systems and more economical than the full blown CLX. There is an ethernet processo (L35E) available for the line.

Everything new we do now is CLX. I have not found any difficulty so far in training the maintenance staff on the CLX platforms - in fact, because of the ability to use fully descriptive long tag names instead of fixed IO, its been easier. The ability to create UDTs enables object oriented programming, which also helps the maintenance staff (provided the UDTs are constructed with troubleshooting in mind).

Be mindful of the ethernet connections. keep control and information networks separated--that is, if all of your processors are on the same net, isolate that net from any "plant" network.

If you have it all together, there will be problems. AB suggests (requires) specific "managed" ethernet switches in such cases. But if all that's on the network is AB, these fancy pancy switches are not necessary

Also Ethernet I/P is OK but I perfer Controlnet. Or acual several tiers. Connect your processors together with Ethernet I/P and do your machine control with Controlnet or Devicenet.

We are specifying ONLY Logix-based platforms here, and are slowly converting older systems over to the Logix platform. We primarily use the 1756-L55 series processors, but have a scatterring of CompactLogix as well.

We've found that they are much easier for the maintenance staff to deal with in general, unless they were programmed by people that absolutely insist on mimicing the SLC/PLC addressing style (curse them). Any programs that come in like that are re-written.

Also, I strongly second bobwithdana.
Keep the I/O and inter-processor communications on ControlNet, and use Ethernet for programming and HMI functions.

I don't really have any problems with the idea of using Ethernet/IP for control except for one, and its the biggest sort of problem: When the IT staff finds a cable that looks like Cat-5, they think its theirs. If they see an RJ-45 socket, they think its theirs. Thats the reason I generally avoid it. As long as they remain clueless about control-net then they will leave it alone. I do connect our PLCs & HMIs to the plant ethernet because its nice to access them from my desk, but I try to locate the controllers and HMIs behind a managed switch.

CroCop said:

Our plant is going to be automating quite a few fairly simple processes, in a distributed fashion. We are looking at using the ControlLogix, Ethernet/IP and FlexLogix. What are things to be mindful of? I'm curious as to the opinions of other users, rather then our local rep's opinion.

Click to expand...

If you're putting in an HMI system. Don't use RSLinx Classic. Use RSLinx Enterprise (or some third party software), and DON'T LOOK BACK!

AK