At the automatic update the OPC server won't sent data that changed less than entered here. The Deadband property is intended only for the analog data (Single and Double data type). The analog value in the OPC server has set the minimum and maximum value.
The update from the server proceeds if:
an absolute value (last_updated_value - current_value)
is greater than
Deadband * (maximum - minimum) / 100
var oOpcGroup = pMe.Pm("/OpcClient/Group1");
var nDeadband = oOpcGroup.Deadband; //Reading the value
oOpcGroup.Deadband = 2; //Writing the value