a large number of tags connected to the CPU in the Rsview32 will affect the CPU ...

hello guys,
these days in one project,i imported about 6000 tags from one Losix5555 CPU to Rsview32 Work and found that the update rate of the HMI was too slow. and when i edited the program on line,the update rate drove me crazy .i should wait for 3 to 4 minutes everytime i made a change.when this occured,i began to check the network and any possible configurations,but all things i did were no use.at last i closed the HMI and found the edit rate online fast.
then should i get the conclusion that the number of tags will affect the CPU?if so,how many tags is the limit?if not, is there any other way to resolve this matter?

thanks!

First of all, why would you import 6000 tags from the CPU. I see this all too often. No forethought put into what you reeally want from a processor. Yes, the HMI polling is probably killing your network with all the traffic. Do you really need all 6000? OR is it a select few that you really want. Some thought about the rate that you really need them is in order as well. In view, you have the ability to set up scan classes. I will bet you have the default 1 second in the foreground and 5 seconds in the background for all scan classes. If using ControlLogix, I believe you need to set up seperatee topics in Linx at different rates in order to control the scans. I could be wrong there, so check.


I will be working with a project that has 9000 tags for 2 pieces of equipment. That is rediculous. I did a project that had 6 of the same pieces of equipment, and I used less than 1000. And even that, I fear was too much. So really, in my never humble opinion, you should consider your application and pare down the tag usage a bit.

David

And yes, your conclusion would be correct. Why? Because your processor only has so much Time Slice to handle communications. Your HMI is overwhelming the comm line and when you add you trying to access as well, it can only give you so much time to handle your reequests because the HMI is innudating it with requests constantly.

You could increase the Time Slice Percentage, but you would only see a minimal increase in performance with a loss of performance in your Programs Scan.

David

I agree with everything David says. Trim it down some if not a LOT.

I believe the update rate for tags is determined by your OPC topic(s) in Linx. The Scan Classes only apply to direct driver conections. I suspect the scan class might be the rate at which the screen would refresh from the OPC topic? The topic will definitely determine the traffic to your processor though.

I have never done multiple Topics to get different update rates, but that seems to me the only way can do it.

Create another topic at a slower update interval. Then point the non-time critical tags at that topic. Should work.

David and RSL,thank you for your reply.

why would you import 6000 tags from the CPU ?

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of course there is no need to put in so many tags.at first i just built a common structure and edit a common routine in Rslogix5000 and imported tags into rsview32 with the tool --"logix 5000 tag import",so every equipment has the same number of tags as the equipment with nessary and most tags.now i had pare down the tags to 3000 and the update is normal now.

I will bet you have the default 1 second in the foreground and 5 seconds in the background for all scan classes.

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I had configured the scan class.important tags are belong to one class with default settings such as command,status,system error ,etc. and other tags belong to another class with 3s in the foreground and 10s in the background.^_^

I believe the update rate for tags is determined by your OPC topic(s) in Linx. The Scan Classes only apply to direct driver conections. I suspect the scan class might be the rate at which the screen would refresh from the OPC topic? The topic will definitely determine the traffic to your processor though.

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yes,RSL,you are right.i changed the opc topic update rate from 1s to 3s then to 5s and got the speed of edit online slowest to slow then to fast.^_^

next time i will not do like this and remember deeply "only import those your needed".

another class with 3s in the foreground and 10s in the background.^_^

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The Scan Classes in RSView32 only apply to connections using the Direct Drivers; if you're talking to a CLX then you're using OPC so your Scan Class settings won't make any difference. If you want to make better use of your bandwidth you have to do what davidg68124 said and make multipe Topics in RSLinx. However it doesn't matter what update rates you set in RSLinx; as RSView32 is acting as an OPC Client it sets the data rate, based on the update rate set in the Node configuration.