Creation of SDEB's for MRP type = VB materials.

Question

Hi Gurus,
When we run plant wise MRP, SDEB's are created instead of Purchase requisitions for all Manual re-order point materials. We understand that SDEB's are created when the stock of tha material is above tha Re-order point, and this SDEB's indicate tha MRP controller whether he can create manually Purchase requisitions or not.
But, we are getting these SDEB's for the materials that have stock below the Re-order point as well. Which is not correct i think.?
For your information, when we run material wise MRP there are no SDEB's at all.
Please explain what might be the Root cause and the solution to over come this..
Thanks for your understanding..
Naveen.A

Answer 1

Dear colleague,
without checking the issue it is difficult to know if there is an error.
Please check if the following information can explain the behaviour of your system:
A)When you do MD01 or MDBT the creaton indicators defines in the
customising are used . whereas when you run MD02 or MD03 the creation
indicator on the individual screen is used.
Single-item planning and total planning follow a different logic
concernng the creation indicators.This is also described in the
documentation for Master Planning/Materials Planning (Chapter 4, Section
2) and in the Implementation Guide.
Single-item planning:
        The entered creation indicators are generally valid.
Total planning:
       The entered creation indicators are used as default values.
       For materials from an MRP group, the values from the MRP group
       apply (if available).
       The creation indicator for delivery schedules can additionally be
       specified per plant. This is used if nothing was specified via
       the MRP group.
       Thus, the priority is as follows:
      1.  MRP group
      2.  Plant
      3.  Initial screen
B)In MD02 system can de multilevel (For components of a header Materia)
or/and Multiplant (Stock Transfre ) planning. In such cases for all the
materials involved the creation indicator used in the screen is used.
C)The creation indicator makes sense only for materials having
procurement type external procurement (F) in material master. For the
materilas which are produced in house (Procurement type E) system will
always create planned orders.
    And Materials having procurement type X(Both procurement types ) is
treated as Inhouse produced material by planning . Thus for such
materials system will always create a planned order. Now this planned
order can be converted into a production orer or into a purchase
order(via purchase Requisition).
    When you run MRP with "Create Purchase Requisition " in the opening
period , then the syetm uses in the opening period defined via  the
scheduling margin Key. In material master , MRP 2 View we maintain
scheduling margin key. And in Transaction OPP1->Planning->Scheduling and
Capacity Parameters ->Define floats we maintain the opening periods per
plant. I am attaching details of Opening period :
   opening period: Opening period is the time which the MRP controller
needs to analyse.Thus he has this buffer with him to rectify any issues
before converting the planned order into purchase requisition.
The opening period is only used in backward scheduling.
Suppose There is a requirement for a material on date =RD1
Let the Goods receipt processing  time  is= T1
Let the planned delivery time =L1
Let the purchasing Processing time = X1
Let the opening period for this material is P1
Time line  for external procurement:
        Planned Del   Pur proc         GR Process
          Time            Time          Time
___|__________|_________|___________|___
              L1            X1         T1
   SD                                         RD1
Now accoring to Basic scheduling:
   Receipt/Requirements Date(RD1)
   Release/Start Date(SD) = RD1-T1-L1-X1
Now let me explain to you when the planned order an purchase
Requisitions are created:
Let us say the date on which you do MRP be MR1
OD = Opening Date
From above diagram :
                                 Opening Per
                                 In Sch Mar Key
__________________|______________|
  XX                          OD                 SD
                                              Release/Start Date
If your MRP date(generally Today) is lying between XX and OD (and
excludind OD)then
MRP creates planned order and if it lies between (and indclind OD)
OD and SD then we create purchase req.
when your MRP date comes between the period OD and SD then you do not
have time left to analyse and therefore instead of you in such cases
forgetting and delaying system automatically creates purchase req.
      In general if , if your order start date or release date is after
the opening period from today then MRP will create planned order.
Oterwise it creates Purchase req.
Check also if you have the note 1063969 applied in your system.
I hope it solves the issue. Otheriwse I think you should open an OSS message with connection to your system,
best regards,
maria