Which logic is followed for Material Availability Check in IW38?

[Oscar_DC]

Hi all,

I recently started doing maintenance availability checks in mass in IW38. The material availability check works correctly, however I do no understand how SAP prioritizes PM orders when they have competing material requirements. I came up with some conclusions via trial and error.

My question is : Is this documented somewhere? I can not find the logic for this anywhere. For example, I don't know if the order priority has an impact on this, or if SAP prioritizes orders that can be completed vs orders that have multiple materials missing ....

Here's what I have so far ...

Note: I am not running MAC upon creation of the order, none of the orders have been released, and my config is set up to look at all material reservations.

CASE 1 : Orders require the exact same amount of material at the same time, orders have the same priority

EXAMPLE:

• Order 1041321 requires 5 pieces of material A. Order start date is 07/19, priority 1
• Order 1041322 requires 5 pieces of material A. Order start date is 07/19, priority 1

CONCLUSION: Which ever order is on top of the list when the MAC is executed will get the material confirmed to it

CASE 2 : Orders require the exact same amount of material at different dates

EXAMPLE:

• Order 1041321 requires 5 pieces of material A. Order start date is 07/19, priority 1
• Order 1041322 requires 5 pieces of material A. Order start date is 07/20, priority 1

CONCLUSION: Which ever order is on top of the list when the MAC is executed will get the material confirmed to it. The date does not impact the material availability check

Any help would be appreciated,

Thanks!

[NTeunckens · Accepted solution]

Please see the following Resources :

• SAP-Note 457787 on FAQ / Notes regarding ATP (Availability To Promise)
• SAP-Note 2219495 related to how to Debug the ATP

In new / high Releases there is a transaction "IW38A" as mentioned in the following resources :

• .PDF Link for S/4HANA
• BlogPost on the SAP Community for "IW38" and "IW38A"