One raw material we assigned base unit of measure as OZ, later add alternate unit of measure as ML. 

Now I wanted to change the base unit to ML and alternaet to OZ.  For that I deleted component from the BOM.  Related PO's, Prd ord and demand are closed.  Deleted the alternate unit from purchasing and plant/stock (Area were we assign the alternate unit), then try to change it giving message as Unit of measure ML used as alternate unit.  (In additinal data screen still the alternate unit and conversion available)

By: Vidhya

You can do the following procedure (after deleting the material in all concerened documents):

1. Delete the uom from Unit of issue field (General Plant Data / Storage 1) in MM if you have mentioned it there.

2. Go to additional data , use delete line tab and delete the conversion factor by keeping the cursor on that line.

3. Come to main data, now change the base unit of measure to the required one.

4. Then give the alternative unit of measure, system will ask for conversion factor.

5. Then save 

You can only change the base units of measure under the following circumstances:-
- No stocks are available for the material.
- There are no existing purchase requisitions, purchase orders, or scheduling agreements for the material.
- At present, no purchase orders or purchase order items are being created or changed.
If requests for quotations, purchasing info records, or contracts are available for a material, the system gives a warning while changing base unit of measure. Still if you want to change unit of measure specify in a dialog box the factor for converting the base unit of measure into the new base unit of measure. The purchasing info records are then, if necessary, updated.

1) If there are stocks in the previous period, you can clear them as follows:
a) Post the stock in the previous period to the current period e.g. 010799 (for example, using movement type 561) so that the stock for the previous period is the same as the stock for the current period.
b) Clear the stock with the posting date in the previous period e.g. 300699 (for example, using movement type 562).

2) If there are Open purchase requisitions, purchase orders, or scheduling agreements for the material.
- Run MM02 (Change Material Master immediately).
- Overwrite the old base unit of measure with the new one in basic data screen.
- Save the change.
- System checks
If a change criterion (MM02) is meeting all necessary prerequisites (as mentioned in point 1).System allows changing base unit of measure. Otherwise it displays warning or error.  You can display the reason for this, by choosing Display Errors (ctrl+F1)

Related

• Material Master Unit of Measure
• Common SAP MM Questions

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