Purpose

• To establish rules as to when to change part numbers and when to change revision levels.
• Changing part numbers when appropriate avoids making a rule for retrofit that says, “all units will be retrofit to the latest revision level.”

Applicability

• All changes processed by this CM function.

Policy/Practice

• The following logic diagram will be used to determine Part Number and Revision Level change:

PART NUMBER CHANGE LOGIC

FRU = Field Replaceable Unit / Service Assembly / Spared Assembly

• Consider all applications of all the items changing.
• Assemblies that are not field replaceable units (FRU) need not change Part Number even though they are not interchangeable (per the logic diagram).
• “Part Number change” will mean a change of only the tab portion of the Part Number.
• Top assembly (Product) will not change Part Number unless Marketing wishes to sell both versions.
• Part Numbers need not change on non-interchangeable change if no parts have been made or if Production Control indicates that all parts made will conform (Pilot Phase parts included).
• Phantom assemblies do not need to change Part Number on non-interchangeable change.
• A parts list change may be interchangeable at the assembly level and, if so, it is a revision level change to the assembly drawing/parts list.
• Parts don’t have revision levels, drawings do. Parts are made from drawings at a particular revision level. If your ERP system demands a rev level change, fool it with a 99 or XX or whatever.
• Revision level is not a part of the Part Number.
• A blind person working in the stockroom with a pick list part numbered in Braille and with the bins part numbered in Braille, must be able to find interchangeable parts. (Most ERP systems don’t issue parts by revision level — thus the ERP is the “blind person.”)

Procedure

• None required.

Primary Responsibility

• CM must keep this standard up to date.
• The CM Manager can take exception to this standard by stating in the applicable change form why it was done.

Authorization