Process Data Cross Reference refers to a cross-reference attribute scheme that has been set up between two classes that share process data to enable the automatic updating of values between objects of these classes when creating and/or updating process object relations, depending on the established cross reference record. The update applies between a Consumer class and Producer class, where the attribute value for the consumer class will be updated based on the change in the attribute value of the producer class. For example, an object of the valve gate class, has an attribute of Flow Rate, whose value depends on on the value of the flow rate of a Process Stream object. By creating a process data cross reference record for the value gate consumer class with flow rate consumer attribute cross referenced with the process stream producer class and flow rate producer attribute, when the value of the flow rate changes for a process stream object, it will ensure that the value for the flow rate changes accordingly for the value gate object as well.
Attributes in different classes sharing the same name are often automatically cross-referenced. Attributes in different classes with different names are mapped manually. By not defining attributes for either class, a dummy cross-reference can be created where the process change is shown but the changed process data cannot be copied in.