How to Configure OPC DA Deadbanding

A deadband is the range a tag's value can vary until it is logged. When a deadband is applied to a tag, it filters out inconsequential data and conserves machine resources.

Configuring OPC DA Deadbanding

• To use OPC DA Deadbanding, the OPC Server must support 'percent' deadbanding, some do not.

• The OPC server deadbanding is defined as 'percent deadbanding' and covers the entire 'Group' .

  • The definition of the OPC server deadbanding can be found in the OPC 2.0 specification at section 4.5.1.6.

• At the 'Group' level in the Canary Logger, the dead band percent number (between 0.0 and 1.0) is passed to the OPC server.

Not all OPC servers support 'percent dead banding', since this is an optional behavior.

• If available, 'percent deadbanding' is the most efficient because it reduces the amount of data that needs to be communicated to the Canary Logger.

In the above example a value of '.10' or 10% has been entered in the OPC Deadband field. This means the logging session omits any value that does not change by more than 10% of the previous value.

OPC UA Collectors support 'absolute deadbanding' while OPC DA Collectors do not.

Setting a deadband on a group of tags is useful for many reasons

• It minimizes network restraints to speed up other processes

• Makes process data easier to visualize with Axiom

• Saves storage space

• Lowers CPU Usage