You define the default values for BOM in OS28.
- Based quantity
- BOM Status
- Size Unit
- Var-size item unit

You control the Material type allowed for the BOM header in transaction OS24.

In transaction OS27, you define the central settings for your BOM management system.  This 
are one-time settings for BOM management, which should not be change after production.

Low date
When you create or process BOMs, the default date is the date defined in your system as the 
earliest processing date (01/01/1900 in the standard system).

BOM validity maintenance
Tick if want the user to specify a valid-from date when maintaining BOMs. If not tick the BOM
created as of the current date or the system low date (1/1/1990).

EC management active
Tick if you want to make historical changes to BOMs with reference to a change number. 
(This means that the status of the BOM both before and after the change is stored in 
the system.)  In this step, you only specify whether engineering change management can be 
used for maintaining bills of material. In transaction OS25, Configure history requirement 
for BOMs, you define whether you want to make the use of engineering change management a 
requirement in certain cases.

Hist. reqmt variant
Use this indicator to control when history requirement applies to new variants or 
alternatives in a BOM group.  

Sub-item documentn
You use the Sub-item documentation indicator to define whether changes to sub-items are 
documented. 

Header
Create BOM header with parameter validity
TECHINCAL TYPE
Mult. BOM inactive
Tick if no multiple BOMs can be maintained in this R/3 system.
Variant BOM inactive
Tick if no variant BOMs can be maintained in this R/3 system

BILL OF MATERIAL ITEM
BOM item explosion type
If you create a BOM item with reference to a change number and change the valid-from date 
(in the change header or alternative date), then this can change the sequence of validity 
periods of a BOM item. The indicator BOM item explosion type specifies whether and according to what rules, 
the system determines a unique change status, when you display, evaluate or change a BOM to 
a date in the overlap period.
Description variable-sized item
This indicator controls which text is displayed in BOM processing for a variable-sized item.

Repeated effectivity via external item ID
This indicator ensures that an item that already exists under an external item ID can be used.

General settings
Unit 'piece'
In the standard system, this field contains a unit of measure for "piece". You can change 
this unit. This unit is the base unit of measure (BOM header) or the component unit of 
measure.

Base unit of measure for:
Equipment BOM
Functional location BOM
Document structure
Standard BOM
Component unit of measure for:
Text item
Document item
Non-stock item without material master record

CAD active
If you want to maintain BOMs from a CAD system, set this indicator. This activates an 
additional field in the BOM header and BOM item, which tells you whether the BOM header or 
BOM item was maintained from a CAD system.


If you deactivate engineering change management, changes to bills of material are not 
recorded.

The modification parameters defined here apply to all BOM categories.

The following settings are made in the standard R/3 System:

1.  Validity date maintenance and engineering change management are active.
2.  The current system date is the default valid-from date.
3.  CAD is active.
4.  Explosion type for BOM item: blank.

SAP PP Transaction Codes
Commonly Used Tcodes in PP Module Part 1
Commonly Used Tcodes in PP Module Part 2
Commonly Used Tcodes in PP Module Part 3

SAP PP Books
SAP Production Planning, Certification and Interview Questions Reference Books

SAP PP Tips
SAP PP Tips and Production Planning/Control Discussion Forum

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