Installation and Upgrade > Windchill ESI > Installing and Configuring Windchill ESI in an SAP Environment > Object Number Lengths in SAP > Object Numbering SAP Number Range Configuration
  
Object Numbering SAP Number Range Configuration
When configuring objects in SAP, there are two number ranges which must be defined for all objects.
Internal number range: The range of object numbers that are assigned internally by SAP when a user attempts to create an object and does not provide an object number.
External number range: The range of object numbers that can be manually assigned to objects either through the GUI or through the API.
Keep the following in mind when configuring SAP number ranges:
Number ranges can be numeric or alpha. In general, alpha-numeric object numbers can be defined for an object regardless of the external number range set.
Internal and external number ranges cannot overlap. They must be unique.
When an object is published from Windchill PDMLink, the object number should fall within the external number range. Exceptions to this are in the following sections, listed by object type.