Usage of checking rules for availability check

[former_member547683]

Dear, all,

at the moment I am analyzing our scope of checks (TA: OVZ9) for documentation and review issues.

I first of all checked all the assignments in customizing/ coding for ATP groups (MTVFP) and checking rules (PRREG).

Unfortunatelly I did not found any general documentation/ hints of the customizing tables which include the prreg.

What I already know is:

PRREG = A - sales order

               AE / BE - SD order make-to-order stock

               AQ / BQ - project stock

               AV / BV - SD order; returnable packaging              

              AW / BW - SD order consignment

                 B - delivery

The SD checking rules are hard coded.

Now I have a lot of Z checking rules.

They are used amongst others in following customizing tables:

TCO11  -  Checking rule for production orders (dependant on order type) ?

T158      -  Tcode dependant checking rules ??

T161V   -   Checking rules for purchasing documents like STO ???

T399D   -  plant parameters - used in MRP? When is this setting used ?

T438M  -  control paramter for MRP? dependant on material type? When is this setting used?

I am not sure if i think in the correct way. Especially the last two tables are not clear to me.

Can anyone give some hints to the usage of the mentioned customizing?

Thanks in advance and

best regards,

Janine

[Former Member · Accepted solution]

Janine,

at the moment I am analyzing our scope of checks (TA: OVZ9) for documentation and review issues.

???  Exactly what are you analyzing?  What issues?  What do you intend to accomplish?  What will be the output of this analysis?  Who will be the recipient of the analysis?

Finding links between fields in tables is a poor way to determine how SAP software is used to solve business problems.   I think you need to first come up with a clear business goal of what you intend to accomplish by the time you have completed your analysis.

With respect to your puzzling Configuration tables, I suggest you enter the tables into SM30, and then hit the "Customizing" Icon.  You will be given a list of customizing transactions that manage these tables.  From here, you can go into configuration (SPRO) and look at the IMG help on each of these transactions, to get a sense of what business issues are addressed by these transactions.

Or, you may decide you want to get a general sense of availability checking.  For this, you should go to the SAP online help, and do some searches.  A good start would be

Availability Check and Requirements in Sales and Distribution Pr - SAP Library

Best Regards,

DB49

[former_member547683 · Accepted solution]

Dear, Dogboy,

You are right. It would be much easier to have a clear business case to analyze.

My 'business goal' is to analyze and document our current customizing settings for availabilty check in general.

I am trying to find out in which business cases the current settings are needed and if they are still valid. Unfortunatelly some of the settings may be obsolete for us. Obsolete ATP groups and obsolete checking rules are just expanding the customizing of the scope of check and make it more difficult to understand. (Especially when you have to duplicate the relevant scope of checks in APO)

I already searched many hours through SCN/ SAP Notes/ wiki documentations and tried to understand the customizing points of the mentioned tables via F1 help on the prreg. I resigned after trying to analyze the where-use-lists to see in which scenarios the settings are read.

I actually missed to read the image activity documentations 😕 I thoung in the past I have not found a lot of answers in there, but in that cases they are pretty good! Thanks for the hint! 🙂

A lot of things are clearer now, but still the last two settings are not completly clear to me...

The image activity documentation is saying:

" In this step, you control the atp check for requirements planning by defining the checking group an the checking rule at plant level or MRP group. The atp check can be carried out in MRP for the dependent requirements. This means that the atp check can directly check whether sufficient material is available for the production of the assembly. The atp check is initiated from planned order processing. It is not carried out automatically in the planning run for each requirement of an assembly. "

Does that mean:

1. If I run the MRP, and only if the MRP is creating planned orders the dependent requirements on component level are checked for ATP with the customized checking rule?

2. If I create a planned order manually (MD11) it is checked for ATP in the same way?

3. There are two customizing tables. One is only addicted to the plant (T399D) and one is addicted to plant and MRP group (T438M). Which MRP group is relevant? The one of the material for which the MRP is running or the MRP group of the components which are checked for ATP?

4. Is it correct: If a customizing entry exists for MRP group, the plant entry for checking rule is not relevant. What is, when a customizing entry on MRP group exists, but no checking rule is maintained behind? No ATP check on planned orders?

Sorry, I am not deep into the production planning process. I am more secure in SD topics.

Thanks,

Best regards,

Janine

[Former Member · Accepted solution]

Janine,

For planned orders, whether created via MRP or created manually, ATP is not performed automatically upon creation.  During interactive processing (MD11/MD12) you have to manually perform this step if you want ATP to be done.  Optionally, it is also possible to perform mass ATPs on planned orders through a report.  

When you perform the interactive ATP check, the system will invoke the checking rule(s) you have configured in OPPQ/OPPR.

Except in the case of Repetitive type manufacturing (where there are no production orders), it seldom makes sense to perform ATP on planned orders in a regular business environment.

MRP Groups are optional.  If your client is using MRP Groups, you will see entries in the Material Master (MRP1 tab).  As a general rule of thumb, when similar settings appear at both the plant level and also the MRP group level, the MRP group setting typically takes precedence, since it is the more granular of the two.

I still don't understand the business case for determining which configuration settings are "obsolete".  In my experience, the effort spent to track these issues down seldom offers any real payback.  It is almost never wise to delete old configuration just because it is 'difficult to understand', since the risk is that you will 'break' something in the productive environment because you failed to understand ALL the business scenarios used by the client.  In your case, where you have already stated that you are a PP newbie, my advice is "don't do this".

In closing, assuming you still want to pursue this quest, let me say this: if I were trying to determine which of the checks were still being used, I would first interview all of the appropriate business process owners about what they think they are still using.  I would also be looking at the objects themselves (e.g. sales docs, Stock Transport orders, Production orders, planned orders, etc etc.)

Best Regards & Good Luck,

DB49

[former_member547683 · Accepted solution]

Dear, Dogboy,

To help you understand:

What would you do if you are working as an inhouse consultant/ developer and nobody knows the original concept of the atp customizing (only some parts of it)? Appropriate business process owners??? 😄 They are more or less just using the atp groups that sounds good. I get more answers when I have a look into the system. Furthermore the knowledge should be documentated (as good as I can) for the future. In addition I shall create some additional scope of checks because of a new business goal.

I just wanted to make sure that I create every relevant combination and not waste my time by creating unnessary combinations.

Of course deleting has to be done carefully...

Hopefully in future some more people have the knowledge about that topic and this research work is only done once.

Thanks for helping me !

BR,

Janine

[Former Member · Accepted solution]

Janine,

What would you do if you are working as an inhouse consultant/ developer and nobody knows the original concept of the atp customizing (only some parts of it)? 

Been there done that.  In this case, based upon your statement that your PP knowledge base is limited, you should be VERY VERY reluctant to change anything that already exists.  This lesson I learned from personal experience.  When things are going along smoothly, no one notices you.  When you break something, you suddenly become very conspicuous.

Appropriate business process owners??? 😄 They are more or less just using the atp groups that sounds good. 

Yes.  However, you still need to get them involved, so that they know what you are trying to do, and they should get the opportunity to veto your proposals.

 I get more answers when I have a look into the system. 

I will say that I learned quite a bit by looking at systems, and then trying things in sandboxes.  However, before I started, I had a good basic knowledge of the subject matter. 

You might want to hire external resources to assist, until you get on your feet.

Best Regards,

DB49