Issue

This document aims to evaluate the potential benefits and drawbacks of copying over custom units of measure (ie no SAP Standard ones) that have been created over time by Syensqo for use with Supplier integration, Ordering and Invoicing. Using non standard UoMs across the system will have impacts any integrations we have (eg between Ariba and S/4) as the UoMs have to be consistent across the entire landscape. 

Recommendation

Start with the Standard SAP / ISO Units of Measure and if absolutely necessary can consider adding additional ones but only if there is no other option.

Background & Context

In the past suppliers who did not send in a standard ISO or SAP Unit of Measure on an acknowledgement, or an invoice would get an error at the point of the data being entered (manually or by interface) on SAP.

This means that the transaction has to be checked and the Unit of Measure corrected by the supplier causing delays – or for the UoM to be added to the SAP UoM list as a custom unit and mapped to the existing standard to avoid recurrences.

The ERP Rebuild will mean a switch to SAP standard as a default.

This could result in going through the same UoM errors that were found in the past and having to correct the supplier or add the custom UoMs to SAP again.

Alternatively, the custom UoMs that have been used to bypass the issue in ECC could also be ported to S4 HANA (and Ariba) to avoid repeating the same errors.

However the use of non standard UoMs will require that any non standard UoM is replicated across all the systems in the landscape which will increase the cost and complexity of implementation, testing and maintenance. 

Assumptions

Not all suppliers adhere to the SAP standard or ISO Units of Measure and will send non standard ones on Acknowledgements or Invoices

Constraints

Impacts

However, it is important to consider potential drawbacks or challenges associated with adding in custom UoMs

• UoMs and mapping will have to be carried over from the legacy system either manually or by some extraction process.
• There is unlikely to be a standard SAP tool to do this copy over as the assumption with SAP is that the SAP and ISO UoMs are enough
• If custom UoMs are present in the system then they could be used by Syensqo staff when creating transactions and master data, rather than using htem to map suppliers own UoMs to SAP standards. This could cause confusion downstream and so a review of how these are currently handled by the system should be carried out.
• If all suppliers are no longer using non-SAP or non ISO UoMs then this may not be a live issue. To decide which ones to carry over a review of UoMs currently received on invoices would need to be be carried out.
• Accepting nonstandard UoMs without proper and complete mapping can cause confusion in standard reports, blocking global analysis.
• There may be legacy data to be transferred that uses these custom UoMs
• UoM mismatches can occur in other streams – eg O2C where customers send in non standard UoMs causing similar issues to procurement.
• If we create custom UoMs they will need to be maintained and validated across the entire system landscape to prevent any interfacing issues.

Business Rules

Any Custom UoM needs to be manually added to the new system and transported through as config. 

Options considered

It would be painful to go through the same UoM errors that Syensqo has already solved by adding in custom UoMs.

However allowing non standard UoMs creates additional complexity and would need to be analysed across the system in order to see how big an issue it is and any downstream or reporting impacts.

Option 1: Use only SAP Standard UoMs, do not copy over any custom UoMs

The organisation uses only the standard SAP offering for SAP and ISO UoMs

Advantages:

• No need to ensure that UoMs are correctly replicated across the landscape
• Reduces the long-term maintenance burden as there are fewer custom elements to manage.
• No effort required to develop a process to transfer the UoMs
• No issue with non-standard UoMs impacting reports
• No potential confusion due to unexpected downstream use of non-standard UoMs
• Ensures that only standardized data is used in the new system, which can simplify future upgrades and integrations.

Disadvantages:

• May hit the same issues that have already been solved when receiving transactions from suppliers
• May invalidate legacy data that uses custom UoMs – e.g. Supplier Invoices and that would need to be altered
• If plan is only to use SAP standards, then another way of correcting the suppliers who send in non-standard UoMs need to be used

Option 2: Carry over any active custom UoMs from As Is

Take over the current custom UoMs as they are, including any mapping

Advantages:

• UoM Problems that are already solved / mapped do not re-occur
• No issue with legacy data that use custom UoMs (if any)
• No impact on suppliers that submit non standard UoMs

Disadvantages:

• Need to replicate custom UoMs across landscape
• Maintenance burden as custom UoMs will need to be supported and .
• Any pre-existing issues (e.g. in reports due to unexpected UoMs) will also re-occur (if we dont correct the data)
• May have an impact on other standard tools or integrations
• Need to develop a process to transfer UoMs 
• Risk of conflicts with standard UoMs and future upgrades or integrations with other systems.
• Potential confusion due to unexpected downstream use of non-standard UoMs
• Need to review data to see which UoMs are actually in use to avoid taking over defunct ones

Evaluation

Based on the evaluation of the solution options, it is recommended that the "Use only SAP Standard" approach is used as a starting position.

This follows the Simplification/Standardisation approach of the project and minimises any maintenance burden going forward.

We can react to any UoM exceptions that occur in testing and data load and review any custom UoM that may be required (but only by exception)

Impact on 3rd Parties

Suppliers and Customers should not be using non standard ISO Codes going forward and should be pushed to do so

Impact on Legacy Data

Need to see how many custom UoMs are used in the legacy data and take action (remap etc) where needed. 

See also

Change log

Workflow history