Network options for upgrade

[digitalfist]

Hi Guys;

We are looking at changing our nework system from DH+ to a faster network. In the beginning our DH+ worked very well but as we added more processors, HMI's and data collection it has severely slowed down the network. We recently recieved our first CLX and installed it on our DH+ network. We have plans to add more CLX processors and change our PLC5 processors to CLX.(data collection reasons)

We have 10 PLC5's, 1 CLX, 8 Panelmate power pro HMI's, 1 Data Collection Computer and 1 PC that is always on the network as it is our PLC programming computer currently on the DH+.

We are looking at splitting the network into 2 networks using the CLX DH+ module as a bridge to help speed up reaction time at the HMI's as a temperary solution. We looked at speeding the DH+ up to 115k but we do not think this will help as we think it's the number of nodes causing our problems not so much the speed.

What I am looking for are some ideas/issues with some faster network systems like ethernet or controlnet. I have read some of the threads dealing with some of these issues but I was hoping to get a little more specific to our situation.

I know that to change to ethernet we will need to change our PLC5 processors to ethernet type but I am not sure about the Panelmates. Maybe it would make more sense to go to controlnet but I have no experience with this network as far as the hardware goes.

Any ideas or forseeable (is that a word?) problems, costing or durability would be appreciated.

Thanks

 

[tom_stalcup]

I know that to change to ethernet we will need to change our PLC5 processors to ethernet type

What model PLC5's are you talking about? Some of the models support ethernet just fine, using a comm adaptor device...

(Our plc5's here use the AB 1785-TR10BT adaptors)

 

[jstolaruk]

For monitoring purposes (SCADA, data collection, HMIs, etc.) I'd use Ethernet. For control (handshaking interlocks) between processors, you could continue to use the DH+ after you've off loaded the SCADA stuff or upgrade to ControlNET if its still too slow.

 

[TConnolly]

I suggest you go ahead and use a Control Logix Bridge. You can put two or three DHRIO cards in a 4 slot rack with an ENBT card (no processor is needed) to form a ENET-DH+ bridge. This will cut the number of nodes on each DH+ network and hopefully solve the problem. Its a lot cheaper than replacing all those PLC5 processors with ehternet PLC5s.

Move the computers to Ethernet and connect them to ENBT in the bridge rack. You can navigate over ethernet onto the DH+ through the bridge - you won't need expensive KTX cards that way.

Use the same technique to move your CLX system to ethernet so its not even a DH+ node.

 

[digitalfist]

This is great stuff!

This is just what I am looking for, some opinons/ideas.

BTW the plc5's we are using are mostly 1745-L20B/E rev.G01

Does anyone know offhand if the panelmates support controlnet or ethernet?

Thanks

 

[Sheldn]

One option may be to continue to use DH+ for you PanelMates and Ethernet for your HMI data collection. The PLC-5/20Es and 5/40Es have the same ports configurable for DH+ or RIO with the addition of Ethernet. You can continue to support DH+ and RIO on the one end and Ethernet on the higher level for data collection. Doing this will segregate the data. DH+ at 57.6 K will have a limit of 12-13 transactions per second. A new transaction is created by HMI to PLC or PLC to PLC and a new transaction is created when ever you acces a different PLC address, data file, data file type or there is sufficient gap between data in the same file. A transaction is 128 words of data max. If your HMI and OIT is not optimized and organized such that you are reading different files and data from all over the PLCs you will create a lot of transactions.

I suggest looking at segregating the networks. The only difference between the PLC-5 and the 5/20E or 5/40E is the Ethernet port will need to be configured with IP address, default gateway, subnet mask etc... Some of the PLC-5s have been put on the silver series. You may wish to ask your local distributor for any special deals for upgrading.

Good luck.

 

[digitalfist]

I would really like to simplify and have the high speed between the PLC's and HMI's. My other problem is I have no ethernet ports at the PLC 5's.

I think I will contact Cutler Hammer and try to come up with a solution.

Thanks guys!