Understand bottleneck entities

A bottleneck entity is identified for each line to determine the line’s performance rate. The bottleneck entity line position is the entity or set of parallel entities in a line that have the lowest expected production rate, and thus limit the rate at which the entire line can produce items.

The entity production rate can vary by whether a job is running or not and by which job is running. Therefore, the bottleneck is not necessarily a fixed entity or line position, but can be determined programmatically (either by MES Web Portal or by MES Stateless API calls) given the current production situation.

The production rate for a set of parallel entities is determined by adding the appropriate production rates of each eligible entity (that is, entities that are not disabled or that can be bottlenecks) and converting them to a common unit of measure (see Line configuration settings). The production rate of the bottleneck entity, or parallel entities, is used as the line's production rate, and the performance amount of the bottleneck entity, or parallel entities, is used as the line's performance amount.

Determination of the bottleneck entity

The bottleneck entity can be determined in the following ways:

• Manually, by specifying a specific entity as the bottleneck entity when configuring the line. In this case, the specified entity is always used to set the line's performance amount. Note that, if there is more than one entity at the same line position as the manually-designated entity, the performance amount comes from all of the entities at that line position. See Manually define the bottleneck entity in a line layout.

• Automatically, by not specifying a specific entity as the bottleneck entity when configuring the line, but by specifying which entities can be the bottleneck. In this case, the bottleneck entity will be determined by the system’s evaluation of entity performance rates for the entities that have been designated as "Can be a bottleneck." See Configure a line layout to automatically determine the bottleneck entity .