The Automatic Scheduling Mode
just plan it allows to set the global scheduling mode either to "automatic"or to "manual. This is done in the Settings dialog and is shown in the plan by the icons for automatic and for manual mode.
Scheduling engine takes over
Automatic scheduling is based on an algorithm that is applied each time the schedule gets modified. The automatic scheduling takes into account the following parameters to calculate an efficient schedule:
- Priorities of jobs
- Successor/predecessor of tasks within a job (routings)
- The resource calendar and their availability
- The release date of a job
- The due date of a job
- "Start not earlier than" or "do not finish later than" restrictions on task level
- Resource restrictions on task level
- The scheduling strategy (ASAP or JIT) applied for this job
Each order has an explicit priority that is specified as sequence number in the "Sequence Number" dialog and this priority together with the available capacities are the basis for the scheduling engine. With the sequence number, the following applies: the lower the sequence number, the higher the priority of the job and the higher its position in the visual schedule.
Whenever you add jobs, or change data like the priority of a job, the scheduling engine calculates a new schedule and shows the impact of these changes immediately. Please bear in mind, that whenever you do changes, only those other jobs can get impacted by the scheduling engine that have a lower priority (higher sequence number) than the one that you just changed. Based on its sequence number the tasks of all jobs are then automatically assigned to the given resource-capacity successively.
So the scheduling algorithm sees to the operations’ placing in time and their resource allocation and other than in the manual mode, resource conflicts are avoided automatically.
Changing the plan
As having been said above, the priority and the available capacities are the basis for an automatically calculated allocation plan. Other than in the manual mode, conflicts can’t be solved by drag & drop (since this is done automatically by the scheduling engine). On the contrary, you have to keep in mind that by moving tasks, you will actively set secondary conditions. If, e.g., you have to postpone a task because certain supplies have yet to be delivered and you move this task, the automatic mode recognizes this as “Task must not start before” and sets a time constraint indicated by square brackets and the clock symbol depending on the the selected planning strategy (ASAP or JIT).
So rescheduling and/or solving time conflicts in the automatic mode should only be done by increasing the job priority or by increasing the resources. In other words, the planner has to decide whether to forward or “accelerate” delayed orders.