SAP Production Planning Table

R/3 does planning without consideration for capacity situations. So if MRP says you need
500 parts on 3/1/04, it schedules them all to be built at the same time, even though you
can only do 100 at a time. Assume you have a fixed lot size of 100, you'll get 5 planned
orders for 100 to start on the same day. This is "Infinite Planning". APO would recognize
that constraint, and instead schedule out the 5 orders over time. The important part of that
is that it also will schedule out the deliveries of the components for 5 different days. This
is "Finite Planning".
Now, assume old fashion MRP. It schedules all 5 orders for the same day, and the buyers
go out an get all of the components for the same day. Then the planner realizes he can't do
all 5, and manually changes the schedule, and manually spreads out the 5 orders. The
buyers will recieve rescheduling notifications, but not until the scheduler does the manual
rescheduling. You could call this "Infinite Scheduling", but that only means the same
thing as Infinite Planning.
But, SAP has "Capacity Leveling". What that means is you run another program after
MRP (CM27 and CM28), which can be run in batch mode overnight. (There is a ton of
configuration and thinking that will be required to do this!). The capacity leveling
program will recognize the constrant at the work center level, and fill up the first day,
then re-schedule the next order to the next available capacity, then the next order searches
for available capacity, and so on. This is called "Finite Scheduling". The problem with
this is the opposite of Infinite Planning, which is it doesn't take Material availablity into
consideration! The system will re-schedule a production order without thinking about
whether the materials will be available or not.
Finite Planning does Finite Sheduling at the same time. If there is no capacity available
on the desired date, the system looks for when capacity IS available. Then it stops to see
if Materials will also be available (usually based on the lead-time for those components).
If there is a material problem, then the system figures out when the materials WILL be
available, and then
checks to see if capacity is available on THAT day, and if so, it blocks off capacity, and
allocates the materials for that day.
Do you have a SAP PP Question?
Difference between MRP vs MPS
Explain the difference between MRP & MPS. Though both components gives you
the requirement list, what we gain out of MPS run rather than running MRP. What
is the main idea behind this?
The following might help in explaining the difference between MPS and its counter part
MRP.
Master Production Schedule (MPS) :
MPS operates within only one level of the BOM, While MRP can be utilized throughout