Process Start and Finish Dates Scheduling (SAP Library

Process Start and Finish Dates Scheduling

Use

The system uses fixed basic dates as the starting point for scheduling a master recipe or process order. Depending on the scheduling type, it requires the basic start date or the basic finish date for this.
Since malfunctions and disturbances can never be fully prevented in the course of a process, you can define additional floats before and after the process. You define these floats in the master record of the material you want to produce.

In scheduling, these floats are used to determine:

The scheduled start or finish date of the recipe or order
One of the basic dates if you have not entered both

Prerequisites

A scheduling margin key along with the required floats has been assigned to the material you want to produce (MRP view)

Depending on the scheduling type, the following basic dates have been entered:

Scheduling type	Required basic dates
Backward scheduling	Basic finish date
Forward scheduling	Basic start date
Only capacity requirements	Basic start and finish dates
"Today" scheduling	Current date as basic start date (automatically determined by the system)

In process orders, you either copy the basic dates from the planned order when you create the order, or you enter them manually.

In master recipes, you enter the basic dates when you start the scheduling function.

Depending on the scheduling type, you only require a date, or a date and a time for the basic dates.

Features

Depending on the scheduling type, the following start or finish dates are determined in scheduling:

Scheduling type	Calculates dates
Backward scheduling	Scheduled finish date, scheduled start date, basic start date
Forward scheduling	Scheduled start date, scheduled finish date, basic finish date
Only capacity requirements	Scheduled start date, scheduled finish date
"Today" scheduling	Scheduled start date, scheduled finish date, basic finish date

The floats defined in the scheduling margin key are taken into account as follows (see graphic):

The float before production is an order float the system adds after the basic start date (BS). It has the following functions in the order:

It can compensate for delays in the staging of material components.
If there is a capacity bottleneck at any of the resources involved, you can move the production dates forwards towards the present. In this way, it serves as a float for capacity leveling.

The end of the float before production is identical to the scheduled start date (SS) of the recipe or order.

The float after production is an order float the system adds before the basic finish date (BF). It can compensate for disturbances in the production process.
The start of the float after production is identical to the scheduled finish date (SF) of the recipe or order.

If both basic dates are entered although the scheduling type requires only one, the system checks whether the scheduled dates lie within the specified period of time. If they are not within this period, it writes an entry into the scheduling log.