This property allows adjusting a minimum variation level of an OPC Tag, so that it can be updated. This property only applies to OPC Tags of an OPC Group that are considered as of analog type by the OPC Server to which the OPC Driver is connected. The valid interval for this property is between 0 (zero) and 100%. A value of 0 (zero) for this property means that any variation in the value of an OPC Tag of an OPC Group implies in updating this OPC Group. This percentage applies to each OPC Tag according to their engineering limits, defined in the OPC Server. To update an OPC Tag, the following expression must be true, evaluated in the OPC Server:

Abs(Previously_stored_value – Current_value) > (DeadBand / 100) * Abs(Upper_limit – Lower_limit)

Default value of this property is 0 (zero).