Dear all,

I'\m researching about making wed base Scada with asp.net(in c#).I deal with some problem:

I find the protocol to connect plc with c# is opc server.But i can't add opc.dll in my program.I don't know how to read and write value from c# to plc.

Please help me solve this problem and share some document necessary.

Regard,

trong

Hello,

in time of internet and also some search servers like Google you can find answer for yourself. For first check your dll creator, then you can find documentation to product. Why I give this sugestion to you? You've post simply nothing specific. How to add DLL to project is depended to your programming SW and also to other important options. So?

Hello trong12

Which PLC do you use?

If you use a S71500 PLC with TIA V14 and V2.0 Formware  you could use the OPC UA Server directly on the Controler.

If not you have to use a OPC Server like Simatic Net OPC Server for accessing the PLC Items for OPC Client in your application.

Bye Murof

Hi,

I sorry to waste your time in my questions but i tried to surf the internet about my project but it doesn't.

Thanks for your mention,i wil save experiment in myself.

Hello,
Have a look here:

Programming an OPC UA .NET Client with C# for the SIMATIC NET OPC UA Server
https://support.industry.siemens.com/cs/us/en/view/42014088

OPC UA .NET Client for the SIMATIC S7-1500 OPC UA Server
https://support.industry.siemens.com/cs/us/en/view/109737901