Maximum Quantity vs. Maximum Release Quantity per Period
The maintenance of quota arrangements permits specifying different types of maximum quantities to be assigned to a certain quota arrangement item:
Maximum Quantity
The maximum quantity of the quota arrangement item lists the maximum quantity which can be acquired by the specified supply source of the quota arrangement item during the validity of the quota arrangement. The maximum quantity will be verified against the quota base quantity and the quota-allocated quantity. The quota-allocated quantity lists the total quantity procured and planned to procure to date from the quota arrangement item source. This value is thereby updated by all the purchase requisitions, planned orders, productions orders, purchase orders and scheduling agreement delivery schedule lines which are assigned to the specific supply source.
The maximum quantity of the quota arrangement item is generally considered by all applications which determine the supply sources using quota arrangements. A quota arrangement item is not suggested as source incase the quota-allocated quantity is equivalent to or exceeds the maximum quantity.
Incase the maximum quantities of quota arrangement items are considered by the MRP then it happens that the last procurement proposal assigned to a quota arrangement item causes that the quota-allocated quantity generally surpasses the maximum quantity of quota arrangement item. This behavior is envisioned by the design of that application.
Generally, the MRP comes with its own set of rules meant for defining the right lot-size for a procurement proposal and these lot-sizing rules are more binding to the logic of the planning run than the maximum quantity of quota arrangement items. However, the modification proposals are available for enforcing the additional lot-size splits during the MRP for considering the maximum quantity of quota arrangement items.
Maximum Release Quantity per Period
The maximum release quantity per period lists down the maximum quantity which a source of supply can make available or supply within a specified timeframe. It thereby, defines the maximum available capacity of a source of supply and therefore it is possible to plan or monitor the capacities.
The maximum release quantity per period is considered only in the account in the planning run within the MRP. It will be ignored by all other applications which utilize quota arrangements during the determination of supply sources (e.g. manual creation of purchase requisitions or planned orders).
As listed in the documentation user can use these values to model something like a maximum available capacity of a source of supply for the planning run. Based on the nature of the planning run the periods maintained there are always measured as "future" periods which are appropriate for the MRP planning. These periods are typically recalculated during any planning run and they move together MRP date (roll-forward logic) over the planning horizon. This is especially the case incase many periods are grouped together (Number of Periods Indicator > 1).
The system verifies during the material planning incase there are firmed receipts (firmed schedule lines, firmed purchase requisitions, purchase orders, planned orders and production orders) in the specified period which have already been scheduled and allocated to the concerned supply source and then this quantity is compared with the maximum release quantity.
However, this is only valid for procurement proposals which are applicable for the MRP. It is possible only for those elements it is possible for determining the concerned period during the MRP run. Those elements which are not considered by the MRP cannot be selected and assessed. Based on all procurement elements which are completely executed or are deleted logically or technically will not be considered even if they are allocated to the concerned supply source in one of the evaluation periods. This is envisioned as these elements do not "consume the MRP relevant capacity" any longer.
In a similar manner, the system ignores the quota base quantities and the assigned quantities of the quota arrangement items. During the planning run, the origin of these is completely unknown and therefore they cannot be assigned to any calculated period.
Based on that this kind of modelling cannot be utilized for controlling the maximum allocation of quantities to quota arrangement item. In contrast to the maximum quantity of a quota arrangement item the maximum release quantity per period is projected for realizing leveling over the planning horizon. It can be utilized for to realizing any source of supply is considered in any period. In the absence of a logic it might happen (depends on the distribution of requirements and lot-sizing parameters specifically in the mid- and long-term horizon) which supplies the sources of the quota arrangements will be allocated very un-leveled to procurement proposals within the planning horizon.
On the basis of the specific business requirements the user has to decide whether to use the maximum quantity of the quota arrangement item or the maximum release quantity per period or both for realizing the desired application behavior.