About items

An item represents one object in a bill of materials and may be a part, sub-assembly, or assembly. An item manages all data associated with one object in a product design, including CAD models and drawings, translations, visualizations, markups, non-CAD documents, and metadata (attributes).

Item numbering

Each item in Upchain is identified by an Item Data Model which is compossed of four parts:

Item Master - The unique identifier assigned at the time the item is created and cannot be removed or reused by another item. The format is based on the rules configured by your Tenant Administrator.
Item Major Revision - Tracks major changes to the item. By default, it is represented by a double alpha-character sequence such as AA, AB, and so on. Newly created items are assigned XX. Based on your organization's policies Tenant Administrators may configure how and when major revisions are tracked. For example, major revisions may include changes to fit, form, or function; cost or price changes; or safety changes.
Item Minor Revision - Tracks minor changes to the item. By default, it is represented by a double numeric-character sequence such as 00, 01, and so on. Newly created items are assigned XX.Based on your organization's policies Tenant Administrators may configure how and when minor revisions are tracked. For example, minor revisions may include adding missing dimensions on drawings; attribute changes; or documentation updates.
Item Version - A version refers to an item with a specific major and minor revision. You may use different versions of an item to test different variations of the item before deciding on one to release. The version number for items in Development is one or higher, for example v1, v2, and so on. A Released item always has an item version of v0.

The major and minor revision as well as version update automatically as you progress the item through different stages of its lifecycle, as explained in the table below.

Item statuses

An item may have one of the following statuses:

Development - The item and all of its files, documents, and attributes may be edited.
Pending - The item is pending release, is usually under review, and cannot be edited.
Released - The item has been formally approved and can no longer be edited.
Obsolete - The item has been marked as no longer in use and cannot be edited.

An item may also be assigned a maturity status. An item's maturity status acts as a label (such as 'Prototype' or 'Production') on a released item. This helps stakeholders, who may only be interested in items at a specific maturity level, to distinguish between the items that are relevant to them and those that are not at the required development stage. Item maturity has no effect on the item version or revision levels.

Note: A released item cannot have child items in development. This is because the parent cannot be considered finished until all of its children are finished as well.

Item lifecycle

An item progresses through its statuses and its major and minor revisions are updated through the use of change requests (CRs) and revisions.

The table below outlines an example of an item's lifecycle. For the sake of simplicity, we are using the default numbering and revision scheme.

Action/Process	Item Data Model	Item Status	Major Revision	Minor Revision	Item Version	CAD File Versions¹
Initial creation (first design phase)	123456789-XX-XX	Development	XX	XX	v1	v1, v2, v3 (file checked in two times)
Send for release with CR	123456789-XX-XX	Pending	XX	XX	v1	v3 (latest version sent for approval)
Release approved	123456789-AA-00	Release	AA	00	v0	v4 (file version also increased to create released copy)
Revise the item (eg. missed dimensions on drawing)	123456789-AA-00	Development	AA	00	v1	v5, v6 (file checked in twice)
Send for release with CR (minor changes made to drawing only)	123456789-AA-00	Pending	AA	00	v1	v6 (latest version sent for approval)
Release approved	123456789-AA-01	Released	AA	01	v0	v7 (file version also increased to create released copy)
Revise the item (eg. need to add chamfer to the design)	123456789-AA-01	Development	AA	01	v1	v8, v9, v10, v11 (file checked in four times)
Send for release with CR (major changes made to design)	123456789-AA-01	Pending	AA	01	v1	v11 (latest version sent for approval)
Release approved	123456789-AB-00	Released	AB	00	v0	v12 (file version also increased to create released copy)

¹_{CAD File version refers specifically to the version of the CAD file and should not be confused with 'Item version'. Each time a CAD file is checked out and either saved or checked in, the file version increments by one but the item version does not.}

Note: When an item is released, Upchain creates a new version of the item that contains a new version of the CAD model and drawings associated to the item, and updates the major and minor revisions. The original item sent for release is given a status of 'Promoted' and hidden from any BOM. However, it is still searchable for historical purposes.

Item attributes

Items contain attributes that describe the item in detail, such as its purpose, function, material, and intended use in the project. There are two types of attributes that you manage in Upchain:

Item attributes - Describe the item and stay with the item regardless of where it may be used (e.g. Material).
eBOM attributes - Describe the item's use in a BOM and change depending on the eBOM the item belongs to, as the attribute is written on the parent level. The default eBOM attributes are:
- Quantity
- Spare (not to be confused with Recommended Spare, which is an item attribute)
- PC/WP (Product Contact/Wear Part)
- MTR (Material Traceability Report required)
- C of C (Certificate of Compliance required)
- Apvl (Customer approval - this can be incorporated into workflows to add additional approval steps)
- Ref Only (Reference Only - this excludes the item from Change notices)

Learn how to configure item attributes.