Efficiency factors in Enterprise Planning

Enterprise Planning uses efficiency factors to take into account variable productivity for lead-time calculation. Various reasons can exist for variability in productivity, such as reduction of work force in the holiday season, or hiring extra work force in busy periods, which, in practice, means that there is more or less available plan time on a certain day.

You can define efficiency factors when you set up a calendar in the Calendars and Periods module of Common. For each time interval, you can specify an efficiency factor. For more information, refer to Efficiency factors.

Lead-time offsetting

If Enterprise Planning performs forward planning, LN retrieves data the applicable start date from the Calendar Working Hours (tcccp0120m000) session, and proceeds forward day by day, repeatedly subtracting the available planning time from the total lead-time until it comes across the date on which the remaining total lead time is less than the total available planning time. This is the end date.

The available planning time on a particular date is calculated according to the following formula:

A = N / E
AActually required working hours
NNominally required working hours
EEfficiency factor
Note

In case of backward planning, the procedure is similar, starting at the end date and proceeding backwards to the start date and time.

Example

You have a lead-time of 10 hours and, in a forward planning situation, the planned start date is 2010-01-15. Two calendar lines exist which contain the following details:

DateStart TimeEnd TimeEfficiency FactorCumulative Time
2010-01-1509:0017:0018 hours
2010-01-1617:0023:000.84.8 hours

 

The lead-time offsetting process is then as follows:

Step 1: Total lead-time minus the cumulative time of the start date:

 10 - 8 = 2

The end date is due to fall on 2010-01-16, as the remaining lead time (2 hours) is less than the cumulative time on 2010-01-16 (4.8 hours).

Step 2: The conversion of the (remaining) lead time to actual hours is:

Remaining lead time / Efficiency factor 
  = 2.00 / 0.8 = 2.5

This means that the remaining lead-time amounts to 2 hours and 30 minutes.

Step 3: LN can now determine the end time by adding up the remaining lead time in actual hours to the start time of the end date:

 17:00 + 2:30 = 19:30

The production order is expected to complete on 2010-01-16 at 19:30.

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