Activate variables statically

Determines the activation behaviour of process variables in the OPC server.

Setting	Description of the
	The variable server registers the process variables with the OPC server according to the configured groups and activates them. Data is therefore exchanged between the variable server and OPC server without any further client request.
	The variable server registers the process variables with the OPC server according to the configured groups. The corresponding process variables are only activated at the request of a client (e.g. when a view is loaded). From this point onwards, the process variable values are exchanged with the OPC server.

Depending on the OPC server selected, this parameter can significantly influence the behaviour of the visualisation application. Normally, the activation of a process variable is not a time-critical factor in the system. The exchange of data should generally be minimised. However, there are exceptions where the exact opposite can be observed due to the internal architecture of the OPC server: While the data exchange between the variable server and OPC server hardly requires any computing power, the activation of process variables drastically reduces the system resources. In this case, the parameter Activate variables statically should be selected.

Parameters for module:

• Variables

• Communication channel (OPC)Communication channel (OPC UA)