Question Re: UOM conversions in IBP... how to deal with roundings vs ERP conversions in Supply Chain Management Q&A

UOM conversions in IBP... how to deal with roundings vs ERP conversions

tgougeon — Wed, 02 Mar 2022 17:04:18 GMT

Dear community,

We are facing an issue regarding the way the UOM conversion was designed in IBP versus what we know from ECC. For example, we have Product A with Base Unit 'CRN' et a conversion rule in ECC of 1 'PAL' = 1023 'CRN'.

In IBP we need to use a conversion factor, in this case 1/1023 = 0,000978 (rounded).

Now if we want to maintain data using the unit 'PAL' in IBP, for example 3 'PAL', IBP saves 3067,484662 'CRN' which makes 2,999999 'PAL' back.

I understand the internal conversion when IBP is saving data is somehow "hard coded" and we cannot set our own formula.

What are your thoughts about this issue?

I have tried to add an additional attribute to the master data type XXXUOMCONVERSIONFACTOR. By doing this and making it an key figure as attribute and adjusting the key figure formula, I am able to show the correct value.

But if I try to maintain a value, it saves using the unique conversion factor way.

Regards,

Thomas

Re: UOM conversions in IBP... how to deal with roundings vs ERP conversions

AyanBishnu — Wed, 02 Mar 2022 22:07:24 GMT

What is base UOM of that product in ECC and in IBP ?

Re: UOM conversions in IBP... how to deal with roundings vs ERP conversions

tgougeon — Thu, 03 Mar 2022 07:30:56 GMT

'CRN' is the base unit in ECC, same in IBP.

Re: UOM conversions in IBP... how to deal with roundings vs ERP conversions

AyanBishnu — Thu, 03 Mar 2022 17:18:23 GMT

If CRN is the base UOM in IBP, then ideally you shuld maintain the UOM conversion factors as follows, since you mentioned that 1 PAL = 1023 CRN

PRD UOM Factor

SKU1 CRN 1

SKU1 PAL 1023

It is recommended to load data in the base UOM which is CRN. But even if you load the data in PAL, lets say 3 PAL, then the data will be saved in the KF as 3*1023 = 3069.

I didnt understand why you need to mantain the 1/1023 = 0,000978 (rounded). ?

Re: UOM conversions in IBP... how to deal with roundings vs ERP conversions

tgougeon — Thu, 03 Mar 2022 21:07:15 GMT

So i have made a few screen shots to illustrate the issue:

Here is the initial situation of my KF, values shown in base unit 'CRN' :

I have set the conversion as you suggest :

Then i display the values in unit 'PAL' :

This is wrong as you can see, with this setting the calculation is 1023 x 1023 for S09 2022 and 2046 * 1023 for S10 2022

Now i set it back to 1/1023, rounded by IBP 6 decimals :

And i get the values :

Where you can see I have the rounding issue.

Now i set 'S11 2022' to value 1 and 'S12 2022' to value 2 and I save. I get the result :

As you can see again i get rounding errors, where in ERP I have exact values because we use fractions.

Back to display in base unit 'CRN' :

For information, here is the calculation formula :

Which is the standard way the models are delivered in IBP.

Re: UOM conversions in IBP... how to deal with roundings vs ERP conversions

rajtiwari — Fri, 04 Mar 2022 05:30:41 GMT

Hello Thomas,

Could you please maintain the unit conversion factor as below and check the result , it may help you

PRD UOM Factor

SKU1 CRN 1023
SKU1 PAL 1

Thanks

Rajesh Tiwari

Re: UOM conversions in IBP... how to deal with roundings vs ERP conversions

manikandan_shanmugam3 — Fri, 04 Mar 2022 15:05:38 GMT

Hi Thomas,

You are facing this issue because you can save only upto 6 decimal numbers in SAP IBP. you cannot save exactly 1/1023 = 0,000977517, instead you can use 0,000977 or 0,000978, either way you will loose/gain some quantities.

Try to convince your business as those are only small percentage due to mathematical errors, or like Rajesh suggested, use PAL as base unit if business agrees to plan at PAL level instead of CRN unit level.

Regards,

Mani

Re: UOM conversions in IBP... how to deal with roundings vs ERP conversions

tgougeon — Fri, 04 Mar 2022 16:33:52 GMT

We have considered this solution but it is not feasible as we do not always have 'PAL' unit. This conversion is just an example, What I am concerned about is the different strategy between S4 and IBP.
Thank you for the input !

Re: UOM conversions in IBP... how to deal with roundings vs ERP conversions

tgougeon — Fri, 04 Mar 2022 16:49:22 GMT

I agree the difference is small but I would expect at least the same precision on unit conversion as we have in S4. And having rounding approximations in the interfaces can lead to confusing situations.

Because in the end, we need to transfer this 33742,331288 'CRN' to S4.
Thank you for your input!

Re: UOM conversions in IBP... how to deal with roundings vs ERP conversions

kendw17 — Tue, 06 May 2025 23:59:59 GMT

I am having the same problem. If I store UOMConversionFactor in thousands, would I have to go into every key figure and change the UOM Conversion to be * UOMConversionFactor / 1000. If I could change it in one place, I would think this might work.