Account assignment category to be used in ME21N -Statistical internal order

Hi Gurus,

I have assigned budget(KO22) for a statistical internal order for budget controlling purpose.

Now I wanted to create a PO in ME21N, so that it should commit that amount in statistical internal order.

As the expenses GL account is used i have to give a cost center, and i have to give this statistical internal order also. So that when booking exceeds the budget amount in statistical order it should display error message.

I tried creating PO with Account assignment group 3 (Cost center +internal order valuated), and i can not see any records in KOB2 or in the report S_ALR_87012993. PO is created even when the PO amount exceeds budget amount.

However it is not allowing invoice posting when exceeding budget.

Can you please tell me with what account assignment group i have to create PO, so that the PO should not be created when the net price amount exceeds statistical internal order amount.

Thanks & Regards,

Diva