Safety Time / Actual Range of Coverage 
Safety Time / Actual Range of Coverage
Use
The safety time / actual range of coverage ensures that the planned warehouse stock covers the requirements of a defined number of days. It therefore serves as a time float and thus works alongside the safety stock, which acts as quantity float.
Prerequisites
In Customizing for MRP, you have defined a period profile in the IMG activity Define period profile for safety time/actual range of coverage and assigned this to the material in the material master.
To do this, you start from MRP in the SAP Easy Access menu and choose Environment ® Current settings ® Define period profile for safety time/actual range of coverage. You do not therefore need any customizing authorization in order to maintain an appropriate profile.
Features
Safety Time / Actual Range of Coverage
The system simulates bringing the requirements forward by the number of days entered and the planning for the receipts, which are created for these requirements in the planning run, is also brought forward by this number of days. Using the safety time indicator, you can control whether receipts are only to be brought forward for planned independent requirements (planned independent requirements and customer requirements) or for all requirements.
The work scheduler defines the safety time / actual range of coverage as 2 days. A requirement exists for January 31st. During the planning run, the system simulates bringing the requirements date forward by 2 days and generates a planned order with finish date January 29th. However, the actual requirements date (January 31st) does not change.
The disadvantage of this procedure is that a procurement element is created for each requirement. The system only summarizes the procurement quantities necessary for the requirements into a procurement element if you work with weekly lot sizes or monthly lot sizes.
Safety Time / Actual Range of Coverage for Time-Phased Materials Planning
Time-phased materials planning is based on the interval between the MRP date and the availablity date of the next MRP date. By using the actual range of coverage, the number of days defined as the actual range of coverage is added to this availability date. Time-phased materials planning is then carried out for the changed period.
Period Profile for Safety Time / Actual Range of Coverage
In certain periods, it may be necessary for you to plan using a different range of coverage from the one that you have defined in the material master. In order to smooth out seasonal fluctuations, you can use the period profile for any freely definable period of time to define a different actual range of coverage from the one that you have defined in the material master. You can thus, for example, set in the period profile that a higher range of coverage than in normal months should be used to cope with increased demand in the months leading up to Christmas.
During the planning run, the system checks whether you have assigned a period profile to the material and whether the requirements date falls in one of the periods that are defined in the profile. If that is the case, the system calculates using the actual range of coverage from the period profile. If that is not the case, the system uses the actual range of coverage from the material master.