Configuration Limits - Communication - Siemens SIMATIC S7-400 Operating Instructions Manual

Application and functions
1.6 Performance data
1.6.2

Configuration limits - communication

OPC functions - OPC UA server
In server mode the CP supports the following configuration limits:
● Number of connections to OPC UA clients
Maximum of 10 connections to OPC UA clients
● Number of items in the CPU data area
For the variables in the data area of the CPU to be written or read as items, the following
maximum values apply:
– Maximum number: 64000 Items (symbols / variables)
– Maximum memory requirements 64000 bytes
The maximum memory area is divided among the variables used for OPC UA. As a
consequence the following maximum configuration limits apply to the different data types
of the variables:
– 64000 variables of the data type BOOL
– 64000 variables of the data type BYTE
– 32000 variables of the data type WORD
– 16000 variables of the data type DWORD
– 32000 variables of the data type BYTE
● Number of supported subscriptions
– Maximum of 5 subscriptions per session
– In total maximum of 50 subscriptions at the same time
● Number of items per subscription
– Maximum of 900 items per subscription
– Maximum of 45000 items over all subscriptions
● Memory depth for MonitoredItems
Queue size 2
16
or
or
or
or a combination of the maximum values listed, for example:
+ 8000 variables of the data type WORD
+ 4000 variables of the data type DWORD
Operating Instructions, 01/2017, C79000-G8976-C427-02
CP 443-1 OPC UA