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Subplan Constraints
There are some constraints in how Windchill handles subplan relationships. It is essential to understand the relationship of plan information in a subplan to parent projects or to programs, to determine how you can take best advantage of the benefits of a subplan. Constraints related to subplans follow:
A plan or plan activity cannot refer to in its own plan. Subplans cannot refer to a plan or activity if there is a cyclic dependency between the plan and activity.
A subplan or plan activity cannot be added as a child of subplan.
All the parent plans must start for a child plan to start.
The start date of a subplan must be later than the start date of the summary activity, if the summary is executing.
In the case of automatic execution, the plan can only start if there are references to the subplans in the Parent Plan.
To create a subplan when the plan is in the state In Process, the subplan must have a reference.
When the Subplan is controlled by predecessors, you cannot add it as a child of summary activity.
Importing the plan in Replace mode using Microsoft Project removes all the subplan references.
The plan could not be imported because one or more of its subplans contains predecessor.
A Plan activity with an MFO constraint cannot have a subplan as its predecessor.
A subplan cannot be added as a child to a summary activity that has an SNET constraint.
Importing a plan in replace mode removes all subplan references.
When importing a subplan in sync mode, the scheduling and tracking attributes in the subplan are executed.
Modifying the execution mode of a plan is not supported. This is true when the plan contains subplans that are referencing objects in other plans, or, objects in this plan are being referred by subplans in other plans. To modify the mode of execution, delete the references.
In an executing or a completed plan activity, indenting or inserting activities or subplans is not supported.