I'm using OPC UA version 8.1 with Windows 7 64 Bits SP1.

I have two main problems when i usit it.

FIRST PROBLEM :

I have written a C# application and I use the dll’s that Siemens put on the web, where I have 1 Session connected to 1 PLC. I have1 group (or subscription) with 2 items that monitor.
All work OK.
The problem comes when I add more subscriptions, they all seem to inherit the first subscriptions items.

In another words if I have 1 item in two subscriptions after one receives an event after the PLC data change in the variable the item in PLC will not receive an event but two events, because I have two subscriptions.

When in the past i used OPC DA I had two groups

• One for Control – updated cyclically at 200ms (with the items in this group with the property IsActive a true and the group property IsSbscribed a true)
• One General – Nerve updated 1000ms (with the items in this group with the property IsActive a false and the group property IsSbscribed a false)

I never had problems ilke this in OPC DA

SECOND PROBLEM :

Sometimes the bits in the PLC stays at 1 (integer) or True (Boolean) forever.

I have had to do some software in the PLC so the PLC detects that a bit is a True more than 2 seconds, then the PLC put a False for 500ms and the put at True again.

I didn't have that problem when i programed in OPC DA architecture, this problem arises when

i change to UA architecture.

I have a Cycle time in the OPC of 100ms. My Cycle when i create the subscription is a value  of 100 (integer that represents 100ms) and the cycle to monitor the item is 100ms.

See the pictures

Hello Rui1234

do you have a Link to the Siemens example where you got the dll´s?

Thank you

Bye Murof

Hi Murof,

I use OPC NET 8.1 with Windows 7 64 SP1.

My communication is throe TCP/IP (Ethernet).

The communication is using OPC UA.

See the zip file in link bellow (The communication OPC – PC is throe DB1 of each PLC)

https://www.dropbox.com/s/illmb7jkvczl4hi/Prf_Siemens.zip?dl=0

The DLL’s I take from Simatic example Programming an OPC UA .NET Client with C# for the SIMATIC NET OPC UA Server.

In this link

https://support.industry.siemens.com/cs/document/42014088/programming-an-opc-ua-net-client-with-c-for-the-simatic-net-opc-ua-server?dti=0&lc=en-WW

The DLL’s the I use are in the link bellow.

https://www.dropbox.com/s/d4rquyspg2oc605/Api_OpcUA.rar?dl=0

The only modifications that I done was:

Change the name of files

Change the code in authentication so I can use the endpoint with(NONE | NONE)instead of(Sign and encode | Basic128RSA15) the change was in

CertificateValidator_CertificateValidation

I can send to you a sample project if you want with PC, please send me your email if you want so I can send you a wetransfer link so you can download.

To answer to your questions that you put in another user topic.

- Which OPC Server do you use? – OPC Server 8.1

- How is your Network configuration? It’s throe tcp/ip

- Is the OPC Server on the same Computer as the Client? Yes

- Which PLC do you use`? I used a CPU 317-2 PN/DP

- if you use a S71200/1500 PLC, do you use optimized block access? NO

Hi rui,

there's another newer client example for .NET applications. I think it's code is easier to understand because it's less complex.
https://support.industry.siemens.com/cs/ww/en/view/109737901

Your example and this one are using the open source .NET stack from the OPC foundation (in different versions).

If you want the news DLLs to work with you could check out the GIT repository of the OPC foundation:
https://github.com/OPCFoundation/UA-.NET/

/Edit: Though I'm not sure if your problem is due to you client or the opc server.

Hi Owei,

You told

“Your example and this one are using the open source .NET stack from the OPC foundation (in different versions).”

How can you see that are in different versions ?

Thanks a lot,

Rui