Access to WinCC as OPC Server

[Former Member]

Good day to Everyone,

I was trying to access WinCC using UDS framework. I installed it on remote server with WinCC. It was successfully started after 2 munites thinking.

When I am trying to query it I see only 10 percent of tags. Many subfolders are empty. Matrikon shows all tags. All triks in documentation can not helps.

How to integrate with WinCC?

Serj

[Former Member]

Sergey,

The UDSs sometimes take some time to load because they cache can cache the namespace (depending on the settings) which could take a lot of time, specially if the backend data source is remote from the UDS, and if the namespace is large. There are ways to shorten this time by introducing a namespace mask which will limit the namespace stored by the UDS, or creating an alias file to pick out the particular tags you want to see. You will get the best startup performance by setting up aliases.

In regards to the OPC DA UDS (Also known simply as the OPC UDS) there are a couple oddities. First the OPC DA UDS does not follow the conventions the other UDSs do when it comes to tag naming. The OPC DA UDS (version 2.5.x) displays the tag names as fully qualified names regardless of forcing the namespace flat or not. Groups, though will not appear if the namespace is set to flat.

Next, if you do a TagList it will only show you the first 250 tags in the Template editor, this is due to an internal limitation setting. The empty groups are due to the way it browses. Only the first 250 tags are returned, meaning any group that displays the 251st tag and beyond, will not show it.

If you find that you need a tag that isn't listed, you can do one of two things, you can either type in the tag name (make sure it is fully qualified) or use a mask (again assume the tag names are fully qualified) to filter the tag list (note that the filtered tag list will also give back just 250 tags).

Lastly, I know that WinCC allows for 'odd' tag names, the OPC DA 2.5.x UDS does not like tags with the following characters [underscore '_', and percent '%'] in it, to fix this you must use an alias file.

Martin.

[Former Member]

Hi, Joe & Martin,

Joe: I am fine and in process of first xMII implementation. -). Let's see how it will be.

Martin:But Unfortunately I am not currently at customer side and can not check your advise with mask and aliases but I see the main idea.

As soon as customer finish the checking I will come back.

Serj

[Former Member]

Hi, Sergey.

As I recall, the WinCC OPC server implementation does not perform well when asked to provide a hierarchial namespace for tag browsing. You may want to change the UDS to use a "flat namespace" model, and I suspect you'll see orders of magnitude better performance. Take a look at the UDS Admin options.

- Rick

[Former Member]

Hi, Rick,

Changing from hierarchial namespace to flat does not help. The configuration of UDS Admin is as default only OPCServerName = OPCServer.WinCC.

Currenly I see only limited list of tags and do not understand the criteria of showing tags.

Serj

[Former Member]

Hello Sergey,

How are you doing?

When you say that you get a limited list of tags - what exactly do you mean? the tag list will only show a limited number of tags.

Have you tried doing a Mask to see tags that may not be shown?

Best Regards,

Joe

[Former Member]

What settings do you have in the UDS Admin for WinCC?