Siemens SIMATIC ET 200AL, System Manual

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OPC UA communication
9.3 Using the S7-1500 as an OPC UA server
Communication
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Settings for sessions
• Maximum timeout for sessions
In this field, you specify the maximum time period before the OPC UA server closes a
session without data exchange.
Possible values between 1 and 600000 seconds.
• Maximum number of OPC UA sessions
In this field, you specify the maximum number of sessions the OPC UA server starts and
simultaneously operates.
The maximum number of sessions is dependent on the performance capability of the CPU.
Each session ties up resources.
Maximum number of registered nodes
In this field, you specify the maximum number of nodes the OPC UA server registers.
The maximum number of registered nodes depends on the capacity of the CPU and is
displayed when you configure the field content (place cursor in field). Each registration ties
up resources.
Note
No error message following attempt to register more than the configured maximum
number of registrable nodes
If a client tries to register more nodes during runtime than the configured maximum number,
the server of the S7-1500 CPU only registers the configured maximum number. Starting from
the configured maximum number of registrable nodes, the server returns the regular string
node IDs unchanged to the client so that the speed advantage gained by registration for
these nodes is lost. The client does not receive an error message.
When configuring, make sure you have a sufficient reserve by taking into account the
maximum number of nodes that can be registered (for example, using the technical data of
the CPU).
Additional information
Details on which ports are used by the various services for data transfer via TCP and UDP, and
what are the points to note when using routers and firewalls can be found in the FAQ
( https://support.industry.siemens.com/cs/ww/en/view/8970169 ).