Additional Windchill Capabilities > Manufacturing Process Management > Transforming an eBOM into an mBOM > Maintaining an mBOM > Creating an Equivalent Link
  
Creating an Equivalent Link
The ability to create, modify or delete equivalent links is dependent on the filter, view, and view hierarchy defined for each object being used. Actions are disabled if they do not conform to a valid view hierarchy. For example, you cannot create an equivalent link if the displayed upstream structure is actually a child view of the displayed downstream structure’s view.
To create an equivalent link:
1. Select the upstream part or assembly containing the part for which you want to create an equivalent link.
2. Select the downstream part or assembly containing the part for which you want to create an equivalent link.
3. Click the icon. The Create Equivalence Link dialog appears.
4. In the Create Equivalence Link dialog enter the following:
◦ Link Description:
A description describing or naming the link between the selected parts.
◦ Link Type:
If empty, an equivalent link is created. If you select Alternate Equivalent, an alternate equivalent link is created.
◦ Occurrence Link Enabler:
Select to allow the equivalent link to be used as a context for the creation of occurrence links.
◦ Carry over from upstream:
Select to allow the attributes from the upstream part to be used on the equivalent downstream part.
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Equivalent links can be created to an upstream object, even if that object is checked out to another user. If the object is checked out to another user the last checked-in version of the object is used to create the equivalent link.
Equivalent Link Preferences
The creation of equivalent links can be modified through the use of the Preference Management. The following preferences can be used to modify creation of equivalent links:
Preference
Description
Maintenance of Equivalent Links to Self
Specifies whether the equivalent links to self, existing for downstream iterations reused as is from upstream, should be updated automatically or manually by end users when there is a change in the upstream structure. Valid option is Manual or Automatic.
Ask To Carry Over During Create or Update
When creating or updating an equivalent link use this preference to define whether or not attributes from the upstream equivalent part are automatically copied to the downstream part.
Force Checkout
Creating an equivalent does not require that you check out the upstream object, such as a part or enterprise data, from which you are creating the link. However, in certain organizations it can be preferable to ensure that no changes can be made to a downstream object without first having that object checked out. For example, a downstream object can be checked out to one user, but a second user can create an equivalent link to that object and potentially affect the work being done by the first user. To avoid this scenario set this preference to Yes. Doing this automatically checks out the downstream object if an equivalent link is created or edited. This preference is only used if the preference Ask to Carry Over on Create and Update Actions has been set to Yes.
Remove Previous Equivalence Links
Determines system behavior when updating upstream equivalent links. By default existing links between part iterations are kept. If enabled however, when a downstream part iteration of an equivalent link is updated all existing links between the downstream part iteration and the upstream part iteration are deleted.
Enable Equivalent Occurrences
Allows for the creation of equivalent occurrences and consumption links when performing BOM transformations.