Unit 6: Purchasing

Lesson 1 · Creating Document Types in Purchasing

Document categories vs. document types

SAP S/4HANA separates purchase requisitions (internal documents, often generated by MRP) from external purchasing documents. All external documents share the same header/item structure and are distinguished internally by a fixed document category. Within each category, customer-definable document types carry the control settings.

Typical reasons for a new document type: a dedicated number range for a special process (e.g. subcontracting only, allowing only item category L), a different header field selection, or a different output layout.

Three-step definition

Step 1 holds the item number interval (step between item numbers), the field selection key, internal and external number range, and category-specific indicators:

Step 2: only assigned item categories are allowed for the type. Some categories exist only for contracts (M material unknown, W material group). Step 3: for each requisition type + item category, specify which PO/outline agreement types and item categories may be created from it. Example: new PO type NX with standard and subcontracting items, created from requisition type NB → four linkage entries (standard→standard, standard→subcontracting, subcontracting→standard, subcontracting→subcontracting). Linkage can be maintained from either side; a dialog indicator issues a warning for exceptional combinations. No linkage is needed between external documents (e.g. RFQ → PO).

Number assignment

Number range intervals (max. 10 characters, internal or external, non-overlapping) are defined per number range object – one for requisitions, one for external purchasing documents – and each document type gets one internal and optionally one external range. Leave the external range empty for internal-only types. Requisitions created by MRP use the planning run number range (can be plant-dependent), not the purchasing one. Contracts distributed via ALE need internal numbering, because release orders created locally get new keys in the central system.

System / configuration steps

1. Define number ranges: OMH6 (purchasing documents), OMH7 (purchase requisitions).
2. Copy an existing document type in the IMG and adapt it.
3. Assign allowed item categories and linkages.
4. Assign a partner schema to the new type (not copied automatically).
5. Test in ME21N / ME51N.

Lesson 2 · Using Document Types in Purchasing

Document types for automatic POs

From Inventory Management: when a GR without PO creates a PO automatically (movement type flag), the document type comes from Define Default Values for Document Type, entry for transaction MB01 (standard NB) – this entry also applies to MIGO.

From requisitions (ME59N), the PO type is chosen in this order:

1. A PO type with the same key as the requisition type, if allowed.
2. If only one PO type is allowed by the linkage, that one.
3. If several are allowed, the default type for transaction ME21.
4. Otherwise the first allowed type.

Version management

A version bundles the change documents produced while a document is processed further, giving a status snapshot. Benefits: easy change tracking, knowing what was transmitted to the supplier, referencing a version in supplier communication, and comparing versions including long texts. Activation: for requisitions per document type; for external documents per document category, document type and purchasing organization.

Item categories

Item categories control whether a material number is needed, whether account assignment is possible/required, and whether GR and IR are possible/required. They are fixed by SAP: you cannot create, delete or change their control; only the external key and description can be changed. Release strategies always use the internal key.

Lesson 3 · Adjusting the Screen Layout of Purchasing Documents

Field selection keys

For each field selection key you set every field as hidden, display, required or optional. Header and item fields are controlled by keys (requisitions have no header field selection); fields on the account assignment tab are controlled by the account assignment category.

Priority when combining keys

All relevant keys are combined; the stronger attribute wins: Hide > Display > Required > Optional.

The same activity exists under Purchase Requisition, RFQ/Quotation, Contract and Scheduling Agreement (overall transaction OMF4 for purchasing field selection).

Lesson 4 · Creating Account Assignment Categories

Key concepts

The account assignment category on an item states which account assignment object is needed (cost center, order, asset, WBS element, sales order…). You can change standard categories and create new ones. Its account grouping code (account modification) is used with key GBB to propose the G/L account (see Unit 5, Lesson 6). Its field selection governs the fields on the account assignment tab.

Settings per category include: GR indicator default and/or binding (must agree with the item category); GR non-valuated default/binding; default to single or multiple account assignment screen; distribution indicator for multiple assignment (quantity, percentage, amount); and treatment of partial invoices with multiple account assignment.

Allowed account assignment categories are defined per item category. Item category controls cannot be changed; if account assignment category and item category disagree, the item category wins. For GR, GR non-valuated and IR indicators: if mandatory in the item category, the account assignment category must not contradict it.

1. Maintain categories with OME9.
2. Define combination with item categories in the IMG.

Lesson 5 · Defining Text Types and Text Adoption

Text types

Long texts describe materials and services or carry extra instructions (packing, delivery). Text types for documents (key + description) are client-independent and defined per document category at header and item level – requisitions have item texts only (their header note cannot be copied to follow-on documents). Defining a text type does not make it print; output is a separate activity (Lesson 6).

Master data: no new text types for material master or info record (info record text descriptions may be renamed). New text types are only possible for the business partner/supplier purchasing organization texts, and must be flagged relevant to be maintainable; for central texts also set the flag in OBT4.

Text adoption

For each text type you define linkages to source texts (material master, info record, supplier, preceding documents such as requisition, RFQ, contract or a reference document) and a copy sequence: the first source that contains text wins. Standard sequence for the PO item text: PO item text (reference document) → info record PO text from the contract → RFQ/quotation item text → requisition item text. So if a requisition references a contract whose info record has a PO text, that text is used and the requisition's item text ignored.

Example: delivery text from requisition with *: if not explicitly adopted, it is active in the PO but gets lost when another PO is created with reference to that PO. If adopted, it is copied further.

Lesson 6 · Specifying Texts for Output Processing

Texts in messages

Per document type and print operation (1 New, 2 Change, 3 Expediter/urging, 7 Order acknowledgment, etc.) you define which texts print and in which order. Header texts appear before the items or in a supplement after all items. Texts can come from the document (object EKKO header, EKPO item), master data (object MATERIAL) or standard texts created with SO10 (text ID ST or own IDs). Standard texts can also be included into long texts: Expand immediately copies the text (editable); otherwise only a link is stored and the current version prints.

Item text output depends on document type, print operation and item category. With print sequence and printing priority you choose one of several texts: e.g. material PO text from the PO item (sequence 1, priority 1); if missing, the material master PO text (sequence 1, priority 2). Only the first existing text of the same sequence/priority is printed.

Forms and purchasing organization texts

The form (SAPscript, Smart Forms or PDF/Adobe) defines the layout; copy standard forms rather than changing them, and assign form and print program to the message type. For plain paper printing, purchasing-org texts (text ID ADRS) supply sender (address window), letter heading (logo), footer and complimentary close.

Printout of changes

Per purchasing document category (PO, RFQ, contract, scheduling agreement – each identified by a one-letter key in this table) you list fields in EKKO, EKPO, EKET, SADR whose change triggers a change message once the document was already output (e.g. EKPO-MENGE; an order acknowledgment entry does not). The change text is chosen directly via a text number or indirectly via a routine (higher priority; e.g. routine 3 checks deleted/blocked items). Change texts are maintained in Define Change Texts.

Lesson 7 · Controlling the Output of Messages in Purchasing

Two output solutions

Output control covers determining output parameters, rendering forms, sending through channels and archiving. On-premise S/4HANA offers classic message determination (NAST) – the on-premise default – and the newer SAP S/4HANA output management (default in cloud). Activation is per application object type, so both can coexist. For conversions from ECC, staying with NAST is usually sensible; for new implementations weigh simplicity of the new solution against its restrictions.

Message determination (NAST)

Messages (print, EDI, fax, e-mail) are created when a purchasing document is created or changed. Message determination is a form of the condition technique: message schema, message types with fine-tuned control, access sequences and condition tables, partner roles, printer determination and change messages. Prerequisites: new output management not active for the object, and a message schema assigned to each purchasing document category. Condition records specify how, when, where and how often a message is sent; without a valid record no message is generated automatically. Proposals can be changed in the document.

Example result: supplier A gets all documents by EDI, supplier B gets certain document types by fax, all others are printed – achieved with condition records in three condition tables searched by the access sequence.

Lesson 8 · Exploring Customizing for Message Determination in Detail

Elements

Determination is performed at header level, so only header fields can be keys and only whole documents are output. Item-dependent output (e.g. plant) is only possible indirectly through partner roles at header level that depend on plant or supplier sub-range.

Worked determination

1. PO type NB for supplier T-SUP01, purchasing org 101C: schema RMBEF1 is read.
2. Requirements leave only NEU; fine-tuned control confirms it for operation New.
3. Access sequence 0001: purchasing org/supplier → doc type/purch. org/supplier → doc type.
4. Only a record for doc type NB exists → medium, printer, time copied to the PO header messages.
5. Check via Messages › Determination analysis in ME21N or Create Purchase Order – Advanced.

Condition records and printers

Records are created in the application (MN04 create, MN05 change for PO; MN01 for RFQ). Enter the partner function only; the partner comes from the document. Language comes from the document header, not the record. Printer determination: printer in the condition record → otherwise, if print parameter “purchasing group” is set on the message type, the printer assigned to the purchasing group → or print parameter S (user defaults). If no printer is found, no message is created (warning on save; enter manually). Print program and form are assigned per medium.

Change messages

The schema-level indicator New message determination for change messages: if not set, NEU must serve both New and Change and manual changes to output parameters carry over; if set, different types can be used (e.g. NEU print for new, ZAEN e-mail for changes). Lost printouts: Repeat output (no repeat marker; change messages cannot be repeated – reprint from spool with SP01).

Condition components can also be reached centrally via NACE (application EF = purchase order). Output can be processed in bulk with ME9F.

Lesson 9 · Explaining the SAP S/4HANA Output Management

Key concepts

SAP S/4HANA output management (output control) is a unified, cross-application solution for cloud and on premise with pre-delivered scenarios, extensible e-mail templates and central monitoring. In purchasing it covers RFQs, POs and purchase contracts.

Business rules

1. Output type (document to output) and dispatch time.
2. Receiver (partner role).
3. Channel (print, e-mail, XML).
4. Printer settings.
5. E-mail settings (template, sender).
6. E-mail recipient (additional addresses).
7. Form template (country/language-specific).

All rules are evaluated; set Exclusive on specific rules and order them from specific to general. Scheduled POs can be output with the Print Scheduled Purchase Orders app or ME9FF (as named in the handbook).

Unit summary & exam focus

T-codes in this unit

Self-check questions

1. Which three steps are needed to create a usable new PO document type that can be created from requisitions?
   Answer

   Define the document type (number ranges, field selection), allow item categories, and define the linkage with requisition document types/item categories. Also assign a partner schema if needed.
2. How does ME59N pick the PO document type?
   Answer

   Same key as requisition type; else the only allowed type; else the ME21 default; else the first allowed type.
3. A field is “required” in one key and “display” in another. Result?
   Answer

   Display (display has higher priority than required).
4. Which takes precedence: item category or account assignment category settings?
   Answer

   The item category.
5. What does fixing indicator N mean?
   Answer

   The text is only displayed from the source; it cannot be adopted or changed.
6. Can message determination in purchasing use the plant as a condition key?
   Answer

   Not directly; determination is header-level. Indirectly via plant-dependent partner roles.
7. Name three differences between NAST and S/4HANA output management.
   Answer

   No preview before saving, no determination analysis, rules in Customizing not changeable in the document, all output stored, no fax.