Network options

I would like to get some opinions on expanding my plant network.
Currently I have 1 slc5/05 running 90% of my assembly line. It has 3 1747-sn networks. 2 sn's are running flex I/O modules scattered throughout the plant, #3 is running a remote slc rack. I also have 7 stand alone machines with various slc controllers, (1-5/01, 2-5/03, 4-5/04).
These are the options I currently have. I have another 1747-sn card and enough adapters to change the machines to remotes running from the 5/05. Or I have enough 5/04's to change all processors in the stand alone units.
So which method would you recomend and why. If you recomned changing to 5/04's can that entire network be made accessable thru ethernet.

What HMI units do you have? What do you need?

I currently have over 130 SLC 5/04 all networked together using DH+ and going through a CLX gateway. I also have about 10 SLC 5/05 on an ethernet network. I can see everything wirelessly from my laptop. Most of my HMI units are either RIO or DH+ from the processor. I can not control everything from 1 plc due to our need to take machines out of service. If I had a PLC, then isolating the machine completely would pose some significant challenges. If you don't have these challenges and 1 processor can handle everything, then that might be an option.

Some things to consider, what happens if you have a card problem and need to replace a card? With 1 system, your plant will have to go down. How big would the program be? Sometimes it might be easier to have seperate processor than a 4000 line program.

I am in the process of changing most of these to SLC 5/05 or CLX processors. I would recommend that you skip the 5/04 and go either to 5/05 (which is probably the easiest due to programming issues) or to a CLX. Network everything together on ethernet and put in a couple of HMI that can access all the machines. Put all this on a managed switch (I use N-Tron) and is will be a lot easier. DH+ (if you network the 5/04) can bog down real bad for some of my systems. In addition, I still have an issue where I can make a change on a processor on DH+ and when I assemble the edits, the communication channel faults our (NOT the processor) and the SLC must be powered off and then back on to reset it. After 11 years, no one in AB has been able to fix it.

It depends on what you will be using the network for, how much bandwidth is needed, and what the various CPUs do.

Making one CPU control everything makes sense if this is one large proces or plant. If they are individual processes, then keep the separate CPUs.
If the single SLC5/05 CPU can handle the jobs of all the other CPUs, then I am fairly certain that the ethernet port of the single CPU will be better than 7 CPUs with DH+.

If you keep the separate CPUs, then to exchange the remaining CPUs to all SLC5/04's, except for the lone SLC5/05, could be a viable option if all that is needed is a little messaging and the occasional programming. If you need to log alarms or proces values from all the PLCs, you should try to keep the data as little and as unfragmented as possible. Also, if the distances are not too long, you should consider to bump up the speed to 230k.