Revision or version
This is the one judgement call in a release. Partix will not make it for you, because it depends on what the change means to the people who use the item.
The difference
| What happens | Revision | Version |
|---|---|---|
| Part number | Unchanged | A new one is issued |
| Version number | Unchanged | Moves up: major, minor or fix. |
| Revision letter | Steps A, B, C. |
Restarts at A. |
| Everyone else sees | The same item, updated. | A different item. |
Which to choose
Ask one question: Can this replace what came before, without anyone needing to know?
- Yes → Revision. The item is still the same thing. A typo fixed, a drawing clarified, a note added, a supplier detail corrected. Stock on the shelf is still good. Purchasing orders the same number.
- No → Version. The item is no longer interchangeable. A dimension changed, a component was swapped for something that is not equivalent, a pinout moved. Someone holding the old one needs to be able to tell the two apart, and a separate part number is how that is done.
The stockroom test
If a box of the old ones and a box of the new ones got mixed together, would that cause a problem? If yes, it needs a new part number.
Choosing the bump
When you take a version, choose how far to move the number:
| Bump | 1.4.2 becomes |
Use for |
|---|---|---|
| Major | 2.0.0 |
A redesign. Not compatible with what came before. |
| Minor | 1.5.0 |
A real change, but the item still does the same job. The usual choice. |
| Fix | 1.4.3 |
A small correction that still needed a new number. |
When the choice is made for you
Two cases where Partix decides:
- Something inside it took a new part number. Revision is disabled. The assembly now contains a different part, so it cannot claim to be the same assembly. See Commit review.
- A first release. An item that has never been committed cannot take a version. Its first commit releases the version it was created at, usually
0.1.0, and letters itREVA. Moving the number up instead would release0.2.0and leave0.1.0behind, having never existed as a release.
Part numbers are permanent
Once issued, a part number is never reused or reassigned.
It refers to that item at that version permanently. This is what makes an old BOM readable years later, and why the identity fields are locked everywhere else in the product.