Understand the determination of performance rates and bottleneck entities

The following behavior governs the automatic determination of entity performance rates and which entities are bottlenecks.

• All entities at the line position with the lowest production rate are designated as the bottleneck entities.

• If entities at different line positions have the same lowest performance rate for the line, the entity (or set of parallel entities) closest to the end of the line is designated as the bottleneck entity.

• The production rate for a set of parallel entities is the sum of the production rate of all of the parallel entities that are enabled. This is true whether the entities are in a standalone set of parallel entities or are in parallel line segments and at the same line position. Note that there must be a path of enabled entities through the line or line segment.

• For an entity to be considered a bottleneck, it has to be configured as capable of being a bottleneck.

• If an entity does not have a utilization reason (meaning a utilization event was never set for the entity, perhaps because the entity was just created), then that entity is considered for the bottleneck calculation. However, if the entity has a utilization reason, then the current utilization reason for that entity must have its Is Entity enabled when this Reason applies? setting selected to consider that entity for the bottleneck calculation; otherwise, it will not be considered.

• To compare production rates between entities at different line positions, the line’s and entities’ production units of measure, batch sizes, and standard items are used to convert the rates to comparable units. This comparison, and thus the determination of the bottleneck entity, can only be performed if item production rates can be converted to comparable units.

• If an entity is running multiple jobs, the lowest production rate of all of those jobs is used for the entity's production rate value when calculating the line's performance rate.

• If an entity is not running any jobs, the next job that will be running on it is used in the performance rate calculation. The next job is determined by looking at the next upstream work order on the line that has a job for this entity. If there are no jobs for the entity in any upstream work orders, then the standard production rate defined for the entity is used (see Configure entities).

Conditions where entity production rate cannot be determined

If the production rate for an entity cannot be determined, then the line’s performance rate and bottleneck entity cannot be determined. Examples of this condition are:

• An entity on which no job is running, there is no upstream job source for the rate, and a default rate has not been defined for the entity.

• A job is running on an entity that produces an item that is different than the default standard item configured for a line and there is no conversion factor between the different units of measure of these two items.