If you enter a change number that has a valid-from date on the initial screen of characteristics maintenance, class maintenance, or classification, the valid-from date is copied from the change master record. Changes become effective on this date.

Initial status:

• If the objects have already been processed with other change numbers that have valid-from dates, you see the change status that is effective on the date of this change number.

• If the objects have already been processed with change numbers that have effectivity, no valid change status can be determined.

Example: You create a characteristic with the valid-from date January 1, 2000. To do this, you enter change number CHG_01, which has valid-from date January 1, 2000. You can change the characteristic with another change number – CHG_02, with valid-from date January 1, 2001 – and enter another allowed value.

You use change number CHG_01 to assign the characteristic to a class, then use this change number to classify a material in the class. When you classify the material, you see the characteristic as effective on January 1, 2000.

If you change the classification with change number CHG_02, you see the characteristic as effective on January 1, 2001, so you can assign the additional value to the material.

You have activated engineering change management for the class type in Customizing for the Classification System.

Engineering change management is always active for characteristics and characteristics of a class.

• You cannot classify an object in a class if the class is not yet effective or no longer effective on the date you enter.

• If engineering change management is activated for a class type, you can enter a date for your search in the Find Objects function.

• You can only use one change number to change characteristics, the characteristics of a class, or classifications on any one date.