Phase partners are phases that communicate with other phases during batch execution. The number of phase partners that a phase can have is defined for the phase class in the DeltaV Explorer. Based on the number of partners you specify, the recipe author can build a phase link group, which lists the phases that can communicate with each other in the recipe.
Any phase used in a link group must be based on a phase class with a number of partners greater than zero (0); otherwise, the recipe will not be loaded.
Typically, a phase link group contains phases that must be synchronized. Earlier in the tutorial, you synchronized transferring the color out of the color tank and into the blender. The synchronization was programmed into the phase logic by adding REQUEST codes to send messages from one phase to the other. Now, you will add phase partners to allow these phases to establish communication during recipe execution.