Process Tags and Unit Tags

Reactor A and Reactor B are in the same process class. Therefore, you must define process tags that define the interface between the batch control system and the generic phase named Heat. The interface requires that you define process tags for phase control, phase status, formula parameters, control buttons, and interlocks. If inputs, outputs, and internal data points are common to each phase, which is the case in this example, they are also be entered as process tags. Any tags that are not common to both of the phase blocks are entered as unit tags. The only unit tag in this example is the Reactor B Pressure Probe.

Each process class tag is a global tag that represents a set of unit tags; one unit tag for each reactor in the class. For example, Reactors-Heat-CS-START is a global tag that represents the ReactorA-Heat-CS-START and ReactorB-Heat-CS-START unit tags.