Trupti,
NI Server Explorer is an OPC client; therefore, in order to see your PLC registers via NI Server Explorer you need an OPC Server for your PLC -- it doesn't matter who the provider of the OPC Server for the PLC is, whether it be
Simatic PC access or another 3rd party provider. What kind of PLC do you have? National Instruments does have software called IA OPC Servers that has OPC Servers for many of the more common PLCs, as listed here.
Doug M
Applications Engineer
National Instruments
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