Execution Control Object (ECO) 
Definition
An ECO is an entity used for controlling the execution of tasks in predefined zones or nodes of a site.
Use
ECOs are defined to limit the number of constraint objects, such as resources, tasks or handling units, subscribed to a zone/node at any one time.
You can define two types of ECOs in Customizing for Logistics Execution ® Task & Resource Management ® Control Data ® Execution Control:
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1. Static ECO
An ECO whereby the allowed quantities of the constraint objects do not change over time.
You create a static ECO
connected to a zone when you
limit the numbers of resourcesthat
can be working in it simultaneously. Since the zone has a fixed capacity which
does not change over time, the allowed quantities of resources within the zone
also do not change.
You create a static ECO
connected to a node when you
limit the numbers of handling unitsthat can be physically located at it at any one
time. Since the node has a fixed capacity which does not change over time, the
allowed quantities of handling units at the node also do not
change.
2. Dynamic ECO
An ECO whereby the allowed quantities of the constraint objects change over time.
You create a dynamic ECO
connected to a zone when you select tasks as the
constraint type. In such a case, the system determines the number of available
tasks by comparing the total number of tasks starting from the zone with the
number of these tasks subscribed to resources. Since the number of available
tasks changes over time, the ECO is dynamic.
Dynamic ECOs control the number of resources which are sent to a zone by taking into account the number of available tasks or task bundles with the resources’ capacities. Thus they are essential for the workability of the semi-system guided mode of task selection, where resources are being sent by the system to a specific zone without any actual task assignment.
You can enable and disable ECOs via the Enable and Disable TRM monitor methods. For more information, see Monitor Methods.