Database table: SHIFT

As described earlier, a shift specifies the set of shift intervals (time periods) used to determine when resources on that shift are “up” or available to work on operations.

Specify shifts in terms of weeks. This weekly pattern repeats for all weeks in the Scheduler horizon. A week starts Sunday morning at 00:00:00 and runs until Saturday at midnight. All periods within a week not specified with an interval period are considered not working, or down. Daily cycles do not automatically repeat. You must define each daily interval separately.

Resources may use more than one defined shift, and the shifts can overlap. The Scheduler considers the resource available during any of its shifts including an overlap period. More than one resource can use the same shift. If you do not specify a shift, the resource is available for work 24 hours per day, seven days per week.

When a shift reaches the end of an up interval, resources on that shift become unavailable. By default, a resource stops processing when its shift ends.

Note: In the Scheduler, when a resource’s shift ends, the load with the allocated resource uses the resource’s Allocation setting to determine whether to wait for the same resource or to try for other resources. See “Resource Reallocation During Interruptions” on page 69 for more information.

Use shifts when the manufacturing equipment or operator follows a regular pattern of up and down periods that make them only available to perform operations during up periods. Two example situations that might require shifts are:

  • An operator group that works on the day shift only.

  • A machine that requires operators goes down during the change between first and second shift, and between the end of second shift and the start of first shift.