What is the scheduling fixed period?

As a reminder, the fixed period role is to preserve the sequence of operations on their machines after a ‘Scheduling from a given date’ optimization (there are nevertheless few exceptions justifying to modify the sequence).

The global fixed period is a setting applied to the whole plan. That global fixed period can be observed in Planning application as a vertical continuous green line. 

The Help > ‘Planning symbols’ menu describes all the graphic symbols used in the Planning application (about the meaning of the link colors, refer to Help > ‘Link colors’).

What’s new in term of graphic representation?

As the new feature Fixed period per machine offers the ability to have a fixed period that varies depending on the machine, a new graphic representation was necessary.

On the following screen ASS1, ASS3 and P2 machines have their own fixed period. The vertical continuous green line has changed: the continuous green line represents the actual fixed period while the vertical dotted green segments are reminding the global fixed period:

What is the impact on the scheduling optimization?

The screen hereabove shows the Planning after running a ‘Scheduling from a given date’ optimization. The operation tag displays ‘0’ for all the operations starting before the end of the fixed period (i.e. starting on the left of the green continuous line). The field displayed in the operation tag is ‘Order #’ that contains the scheduling iteration number when the operation was scheduled. ‘0’ means not scheduled, confirming that the variable fixed period has been respected.

Of course, this new feature does not change the result of optimization after launching a ‘Total scheduling’ that never takes into account fixed periods. Only the ‘Scheduling from a given date’ optimization takes the fixed period into account.

How to activate this new feature?

It is possible to take into account the machine fixed periods by selecting the ‘Use machine fixed periods’ checkbox at Optimization > ‘Constraint configuration’, in ‘Periods’ tab (this is the same tab where global fixed period is defined):

Defining the fixed period of machines has to be done in Data Module at Grouping / Machine level, in the machine ‘Detail’ tab.

The parameter is set in Days and Hours in the ‘Fixed period:’ field:

To be taken into account, the machine fixed period specified must be larger than the global fixed period (global fixed period can be seen as a minimum fixed period).