Limits Inheritance
To reduce the limits configuration effort, the application allows limits to be inherited under certain circumstances and vary based on characteristic context. This inheritance mechanism also allows defining overrides.
 |
EXAMPLE: A specific equipment could require narrower limits so the equipment limits would override the parent equipment’s default limit.
|
Limits can be configured on a product type, which applies to all products of that type, and it is possible to override these limits for some products. There are two (2) types of inheritance that will be used together or separately depending on context. See the “Retrieval Logic” section under each context section below for details on limits inheritance usage.
By Product Type
When requesting a limit for a specific product, if the requested product does not have a limit defined, the application will look for the same limit on the product’s product type. If the product type does not have a limit defined either, the application will look for product-less limits. If a product does not have a product type configured, product inheritance cannot be used. Lets say that we have Product 1 of Type A and the following limits are configured.
• Requesting limits for Product 1 from 2:00 would find the limit value of 30 on the product itself.
• Requesting limits for Product 1 between 1:00 and 1:59 would not find limits on the product itself but would inherit from product type Type A the limit value of 20.
• Requesting limits for Product 1 before 1:00 would not return any limits.
By Equipment Hierarchy
When requesting a limit on a specific equipment, if the requested equipment does not have a limit defined, the application will successively look for the same limit on each parent equipment going up one level at a time, stopping when a limit to use is found or if top-level equipment is reached of that equipment’s hierarchy. Let’s say we have the following equipment hierarchy, and these limits are configured in the application.
• Requesting limits for Line001 from 3:00 would find the limit value of 30 on the equipment itself.
• Requesting limits for Line001 between 2:00 and 2:59 would not find limits on the equipment itself but would inherit from the 1st level parent equipment WorkCenter001 the limit value of 25.
• Requesting limits for Line001 between 1:00 and 1:59 would not find limits on the equipment itself but would inherit from the 2nd level parent equipment Area001 the limit value of 20.
• Requesting limits for Line001 before 1:00 would not return any limits.
When both inheritance methods are used simultaneously, the product will have priority over the equipment, meaning that the logic will go up the equipment hierarchy with the product before using the product type inheritance. The retrieval logic will be in this order:
1. Equipment AND Product
2. Parent Equipment AND Product
3. Equipment AND Product Type
4. Parent Equipment AND Product Type
5. Product
6. Product Type
7. Equipment
8. Parent Equipment
Unless specified otherwise in each context, when an equipment is part of the retrieval logic, the next retrieval step will go up the equipment hierarchy. The logic will then move on to the product type-based retrieval logic.