Finite planning in PPDS Planning Run

[Former Member]

Hi Experts,

Currently we are running Production planning run in PPDS using MRP 002 heuristic which does infinite planning. Lot size heuristic is assigned in the product master.

After the planning run the schedulers are Going to the DSPB and rescheduling all the orders manually so that it respects the setup groups and keys. In order to reduce schedulers burden i want to run the rescheduling heuristic as a second step in Production planning run. I always thought this is not possible. I have referred to some Notes which tells me that resceduling has to be a manual activity and cannot be incorporated in planning run. I am aware that in the interactive planning-Variable heuristic we can call finite planning heuristic and plan but cannot be done in the production planning run.

Just wanted to put this across to wider audience and take confirmation that finite planning cannot be done as a second step after MRP heuristic run. P{lease come back with your thought.

Thanks

Raghu

[Former Member · Accepted solution]

Sanju,

 I have referred to some Notes which tells me that resceduling has to be a manual activity and cannot be incorporated in planning run. I am aware that in the interactive planning-Variable heuristic we can call finite planning heuristic and plan but cannot be done in the production planning run.

Well, I have never seen such notes.  There are Heuristics for Scheduling, just like there are Heuristics for Planning.  Such heuristics can be run in the Planning job, and they can utilize finite planning.

The catch is, you have to know exactly what you want to do.  I would say that if all of your planners are using a common scheduling heuristic, and blindly executing it without any manual intervention, then you can also run either the same heuristic; or one with the same functionalities; right after the MRP heuristic.  Scheduling heuristics are commonly run within the planning jobs in mature implementations.

This is one of those areas where substantial testing is usually warranted prior to implementing in production.

Best Regards,

DB49

[Former Member]

Hi,

Dogboy is right. I believe you are confusing the meaning of those OSS notes.

What SAP first advised not to do (and in the later versions, even removed the possibility), was to do MRP with finite scheduling. What this means is the following: when you do MRP, you do two things: 1) you decide how much to produce and when you need it, and then 2) you schedule the orders. MRP does both things at the same time (decide quantities, schedule orders), and what SAP says is that it is better to configure MRP to schedule orders infinitely, as the heuristic that creates and schedules the orders (typically SAP_PP_02) has not enough capabilities to handle well finite sequencing.

SAP suggests to first do an infinite capacity MRP, and then run a separate finite sequencing process (typically with many different steps combining the several DS heuristics available). I will agree with SAP on this: finite sequencing is not trivial, and if you start with the result from a finite MRP, you will just make your life more difficult.

regards,

J.

[Former Member]

Dogboy and James,

In our case Planning is usually run for the next week level by level. For example. In the first step the Finished goods planning is run. Then the planners will go to DSPB and run Finite rescheduling for all those FG from th earliest date. The they run the Planning for the Semifinished.

Now i wanted to do the finite rescheduling of orders as a second step in production planning run and the third step for semi finished.

If this is possible, Can you tell me which heuristic shoul i use in the planning run as a second step for rescheduling the FG orders. Your suggestion will be highly appreciated.

Thanks

Raghu

[Former Member]

Hi,

if the procedure is always the same, you can try to set up a planning job with /SAPAPO/CDPSB0 that reproduces the same steps. If the planner is not manually selecting the orders and is happy with the results obtained, just replicate his job (same heuristics he is using now, same scheduling strategies, resources, etc...). You can of course sequencially combine MRP and these heuristics in the same run in the order you suggest.

After the MRP, try something like:

1st step: function/heuristic = deallocate, planning objetc=orders

2nd step: heuristic = SAP005 (schedule operations), use the same scheduling strategy profile the planner is using, planning object=resource

for some reason, you use different boxes for both steps (just by chance, 1st box for 1st step, 2nd box for 2nd step).

Try it first in a simulation version!!

thanks,

J.

Message was edited by: James S.A.

[former_member189901]

Hii Sanju,

You also can run Multi resource planning (SAP_REM_001 or REM_002 Heuristic). It takes consider Planning and scheduling as well. so no need of extra scheduling heuristic..

The primary task of theheuristic is to eliminate capacity overloads that typically occur due to

periodic requirement fluctuations in infinite scheduling. This happens when production is distributed across alternative resources or relocated to preceding periods.

The 'Multiresource Planning (Primary Resource)' heuristic is used to create a feasible, medium-term, finite production plan. 

But it has some constraints. it is has been designed for a typical repetitive manufacturing industries. You can go through the SAP Note 584051 for more details.

Regards

Debashis