Basic dates and Lead time scheduling (MRP Parameters)

[Former Member]

For a material FERT, I have created a monthly requirement of 1000 pieces for 5 months from January to May in MD61. MRP is run for FERT using basic dates as MRP parameter. I repeated the MRP run using lead time scheduling.

I changed the monthly requirement to 100 pieces for all the 5 months and repeated the MRP run using basic dates and also using lead time scheduling.

I again changed the monthly requirement to 10 pieces for all the 5 months and repeated the procedure above.

For the monthly requirement of 1000 pieces, dates corresponding to 5 planned orders obtained using basic dates exactly matches with those created using lead time scheduling. This is the case even for 100 pieces and 10 pieces.

Why is it the case that there is no difference in the way planning was done in both the cases (basic dates, lead time scheduling)?

[Former Member · Accepted solution]

Hello Sethuraman,

The fundamental difference in the scheduling types in MRP parameter is, the basic date makes use of in-house production time maintained in the material master for planned orders. While lead time scheduling makes use of the routing data for scheduling of your planned order.

If you are not finding any difference then check & ensure your routing data as well as the work center in it that they all have mentioned with all the formulas for scheduling. Also to check that the scheduling is working fine in the routing you can follow the path in routing change or display, extras-> scheduling-> schedule.

If you find that the routing is fine then you need to run MRP with planning mode as 3- Delete and recreate planning data as one of the MRP parameter along with scheduling parameter as 2- Lead Time Scheduling and Capacity Planni.

Hope this helps.

Mangesh S

[rupesh_brahmankar3]

Hi Sethuraman,

Please check in OPU5 Adjust basic dates" has been chosen for the scheduling parameters

During the MRP run, a planned order will be always firstly scheduled backwards according to the in-house production time defined on the material master. In this process, system considers the requirement date and schedules the planned order backwards to calculate the basic start date.

The order finish date of the planned order is generally not adjusted by scheduling since it identifies the requirements date of the material

The basic finish date will be only adjusted if the basic finish date initially calculated is after the requirement date. That generally occurs when basic start date is calculated in the past and system automatically switches to forward scheduling and if the production finish date is less or equal the requirement date. Also, the basic finish date will be adjusted to match the requirement date.

When you are creating a planned order manually, however, the basic finish date is adjusted, since there is no restriction regarding the requirement date of material.

System is working as designed and it cannot be changed.

You should make sure that the in-house production time defined on the material master is as close as possible to the times defined on the routing, so that the basic finish date matches the production finish date. Transactions CA97 or CA97N can be used to update the in-house production time with the information from the routing.

Please refer 534380 - No adjustment of order finish date after lead time scheduling.

152319 - Consulting: Scheduling of planned order for routing

Regards,

R.Brahmankar

[former_member206498]

Hi Sethuraman,

Check whether the "In house production time" parameter in the MRP 2 view in material master is the same with total lead time in routing for the specified quantity. You can also update that parameter based on value in routing using CA96/CA97 transaction.

Regards,

Julian

[Caetano]

Hello

On the tab "work scheduling" of the material master you can define a lot size dependent processing time. If this value matches with the values defined on the routing, the basic dates calculation will always match the lead time scheduling. Generally, this happens when CA97 is used to update the material master with the routing data.

You should also consider something very important. If the planned orders is lead time scheduled once, it will also be lead time scheduled on the next MRP execution, even if you set the basic dates calculation for the MRP.

BR

Caetano