About Blocked Demands

This topic applies to APS. When the APS Planning activity projects that a demand cannot be planned in the time between the due date and the current system time (that is, the demand will be late), it push plans the demand forward from the current date out to an as-soon-as-possible date. If, during this push plan, the system cannot plan the demand to be complete before the end of the Plan Horizon, the demand is "blocked," and cannot be planned. The "blocked" message may appear on the Planning Detail form.

Avoiding Blocked Demands

To avoid blocked demands, try these solutions:

  • The easiest solution is to increase the length of your Plan Horizon on the Planning Parameters form.
    Note:  We recommend you specify the same amount of time for the Plan Horizon and the Days to Schedule value on the Shop Floor Control Parameters form, which acts as the horizon for the Scheduler (note that the Plan Horizon is expressed in hours).
  • Increase the length of the shift intervals for the appropriate Resources (do this on the Shifts tab on the Resources form).
  • For the item on the blocked demand, review the purchased item lead times to see if they are realistic and adjust them if necessary.
  • For the item on the blocked demand, review the operation times to make sure they were correctly defined and fix them if necessary.
  • For the item on the blocked demand, check the Resources tab on the Current Operations and/or Job Operations form and set the Break Rule to Shifts.