Primavera P6 Calendar Settings

Where Primavera P6 can create confusion by using standard calendar settings, our software provides relationship free float in days based on defined working periods. Calendars in P6 provide flexibility for managing schedules with different standard work weeks and disparate work exceptions, requiring users to maintain two types of calendar settings:

  1. Hours Per Time Period is used for converting a day into standard hours and allows users to manage schedules at the day granularity.
  2. Work Hours defines periods when work can occur, which P6 uses to allocate durations during CPM calculations.

The user is responsible for managing these independent settings consistently or CPM results will be incorrect. For example, Task A will be performed on the standard 8-hour per day schedule, but the user modifies Work Hours of two specific calendar days to reflect 12-hour days.

Although schedulers refer to task durations at the day granularity, P6 calculates at the hour granularity for purposes of storage and calculation. P6 also uses Hours Per Time Period to convert calculation outputs from hours back to days for the user, based on the User Preferences settings.

P6’s use of Hours Per Time Period creates confusion when converting CPM output such as float, as P6 fails to consider any modified Work Hours. In the Task A example above, P6 converts hours back to days based on the standard 8-hours per day and does not consider the two 12-hours days.

We believe P6 should use the Hours Per Time Period setting only to convert user-defined durations and not for converting calculation outputs such as float. Instead, P6 should calculate based on specific Work Hours.

Task A’s output from P6 varies greatly based on the standard calendar settings and the modified assigned hours. P6 would convert 24 hours of relationship free float into three days, based on the standard 8-hour work day setting, even though two days had working hours set to 12. Based on the full scope of the calendar, the relationship free float is actually two days, showing more critical.

Rather than converting to days post calculation, our software calculates relationship free float in days simultaneously to calculating in hours based on the full scope of the working ranges.