A correction surrounding the Users Preference Setting (UPS) issue affecting calendars which was employed in Primavera P6.7SP1 & P6.7 SP2 & SP4 has not solved the problem described by Rufran's Primavera Scheduling Tips & Tricks 01-13 (UPS). Tasks not using calendars aligned to the UPS or Admin Setting remain a problem. For example: a one day 10-hour activity will take two days because the default “Time Period” is set to 8 hours instead of 10-hours. These are just one of the many unwanted variances that needs to be addressed. Read on and learn what this is all about.

1. Primavera Scheduling
Tips and Tricks 07-13
Proper Calendar Calculations and Settings
Managing Calendars Effectively
2013
Rufran C. Frago, P. Eng., PMP®, CCP, PMI-RMP®
Revision 0: August 26, 2013

2. 072213-Rufran's Primavera Scheduling Tips & Tricks 06-13 Page 2 of 11 9/3/2013
Author: Rufran C. Frago, P. Eng., PMP, CCEC, PMI-RMP
TABLE OF CONTENTS
PAGES
1.0 SITUATION/PROBLEM .......................................................................................... 3
2.0 RELATED TOOLS ................................................................................................... 3
3.0 DEFINITION.......................................................................................................... 3
4.0 PROBLEM ANALYSIS (PA)...................................................................................... 3
5.0 EXPLANATION/SOLUTION .................................................................................... 4
6.0 REFERENCES......................................................................................................... 4
7.0 ADDITIONAL READING MATERIALS....................................................................... 4
8.0 FOOD FOR THOUGHT........................................................................................... 4
9.0 ILLUSTRATIONS.................................................................................................... 5
9.1 BACKGROUND INFORMATION.............................................................................. 5
9.2 REQUIRED SETTINGS ............................................................................................ 5
9.3 ACTIVITY DURATION AND SCHEDULE LAGS CALCULATION.................................... 6
9.4 CALENDAR FOR SCHEDULING RELATIONSHIP LAG................................................. 7
9.5 COMPLETING ALL OTHER CALENDAR ATTRIBUTES................................................ 8
9.6 DEFINING DEFAULT HOURS PER TIME PERIOD IN CALENDARS .............................. 8
9.7 REFERENCE TABLE FOR DEFINING THE TIME PERIOD IN YOUR CALENDARS......... 10
10.0 INDEX ................................................................................................................ 11

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Author: Rufran C. Frago, P. Eng., PMP, CCP, PMI-RMP
1.0 SITUATION/PROBLEM
1.1 The User notices that some of the durations and dates do not make
sense. The floats and variances are also dubious.
1.2 The labor hour per period is not right.
1.3 A correction surrounding the Users Preference Setting (UPS) issue
affecting calendars which was employed in Primavera P6.7SP1 & P6.7
SP2 has apparently not completely solved the problem.
1.4 The complete background information pertaining thereto can be
found by reading Primavera Scheduling Tips & Tricks 01-13 (UPS).
1.5 There are tasks not using the calendars aligned to the UPS remains a
problem. For example: a one day 10-hour activity will take two days
because the default “Time Period” is set to 8 hours instead of 10-
hours.
2.0 RELATED TOOLS
2.1 Project Management (Primavera 6.1 SP1, 6.2, and 6.7 SP1/SP2)
3.0 DEFINITION
3.1 The term “User” in this document is the person using the Primavera
scheduling tool. He can be the planner, the scheduler, the Project
Manager or anyone.
4.0 PROBLEM ANALYSIS (PA)
4.1 If the Admin Setting for Time Period is set to 8-hour per day, then all
activities with an 8-hour per day calendars will not be impacted.
4.2 All activities with more than 8-hours per day calendars will not show
the correct Duration although the dates are correct.
4.3 Adjusting the durations will not rectify the issue.
4.4 Similarly, if the Admin Setting for Time Period is set to 10-hour per
day, then all activities with a 10-hour per day calendars will not be
impacted.
4.5 The situation was further investigated and found to be very common
to most Users.

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Author: Rufran C. Frago, P. Eng., PMP, CCP, PMI-RMP
5.0 EXPLANATION/SOLUTION
5.1 The issue on EDITUSERS PREFERENCESHours per Time Period must
be corrected.
5.2 Fixing the Admin Setting will correct the problem.
5.3 The following changes must be completed for each “Project Specific”
calendar by each schedule owner.
5.4 The “Global” calendars must be changed by the Primavera Database
Administrator.
5.5 Follow the instructions in Figure 1 to correct the problems.
5.6 While you are making the changes, you should consider making the
additional changes outlined in Section 9.2 Required Settings.
5.7 Take Note of Section 9.3 and 9.4 explanations on activity duration and
schedule lag calculation affected by calendar settings and lag
calculation preference (see Figure 2 and Figure 3).
5.8 For uniformity in defining default hours per time period in calendars
across the scheduling database, read Section 9.6 and the
recommended Reference Table for defining the time period.
6.0 REFERENCES
6.1 Primavera Scheduling Tips & Tricks 01-13 (UPS) written by Rufran C.
Frago.
7.0 ADDITIONAL READING MATERIALS
7.1 None
8.0 FOOD FOR THOUGHT
8.1 Users should not use any calendar without inspecting the calendar
first and what are the projects using it. If it does not belong to the
same project portfolio, it is best to create one’s own.
8.2 Caution: Be careful in using a calendar that was not fully defined or
perhaps, does not cover the intended period required by your project.
For example: Project A Construction Phase is supposed to run for two

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Author: Rufran C. Frago, P. Eng., PMP, CCP, PMI-RMP
years until December 31, 2015 but the calendar assigned to the
activities, although correct, were only defined until November 1, 2014.
9.0 ILLUSTRATIONS
9.1 BACKGROUND INFORMATION
The Hours per day on this 4-day, 10-hour per day calendar is defaulting to
8-hours per day, 40-hours per week, 172-hours per month and 2000-
hours per year. This time period values have to be changed based upon
the specific calendar.
Figure 1
9.2 REQUIRED SETTINGS
a) Referring to Figure 1, click the Time Periods button shown and
change the values to the correct values of the project’s specific
calendar.
b) There is a need to set the field called “Inherit Holidays and
Exceptions from Global Calendars” not to reflect any other

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Author: Rufran C. Frago, P. Eng., PMP, CCP, PMI-RMP
calendar or global default. This particular field should be set only
to <NONE>. The reason for doing so is that whenever there is any
change to that Calendar or Global Default Calendar where the
specific project calendar inherited its attributes, the changes will
likewise apply to the specific project calendar. The changes can
occur without the knowledge of the projects.
9.3 ACTIVITY DURATION AND SCHEDULE LAGS CALCULATION
Primavera uses the hour unit in its calculation. When F9 (calculate) is
pressed, the existing activity durations and lags will use the time
period setting of your specific project calendar.
If it is wrong and misaligned because it is using the inherited attributes
from another calendar, then a correction must be made as described
in Section 9.2.
Do not correct the lags without correcting the Time Periods first and
setting the “Inherit holidays…” field to <None> as shown in Figure 2.
Figure 2

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Author: Rufran C. Frago, P. Eng., PMP, CCP, PMI-RMP
Warning: Be on the lookout for calendars inadvertently set to inherit
the default calendar. It can result in misaligned Time Period settings.
The Default calendar set by the Primavera Database Administrator
should not be changed by any User. ***It is unfortunate that at this
time, the agreed-to default setting cannot be locked.
9.4 CALENDAR FOR SCHEDULING RELATIONSHIP LAG
The result of calculating predecessor activities using an 8-hour per day
calendar and successor activities using a 10-hour per day calendar
shall depend on how a User sets the “Schedule OptionsCalendar for
Scheduling Relationship Lag” field as shown in Figure 3.
Figure 3

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Author: Rufran C. Frago, P. Eng., PMP, CCP, PMI-RMP
9.5 COMPLETING ALL OTHER CALENDAR ATTRIBUTES
It is very important that the required attributes of the Global and
Project calendars are completely addressed. It means that the
calendar should reflect holidays, work time-off, exceptions, low
productivity days, weather modeling inputs, and others. The attributes
should cover the whole of the project timeline. If the project is from
2014 to 2018, make sure that the calendar attributes covers the whole
period and not just up to 2016.
Believe it or not, this kind of careless omission is very common
especially with those planners & schedulers who grab existing
calendars from the selection window.
9.6 DEFINING DEFAULT HOURS PER TIME PERIOD IN CALENDARS
 P6 calculates and stores time unit values in hourly increments, but
you can set preferences to display time units in other increments,
such as days or weeks.
 The values specified for Hours per Time Period are used to convert
hours to other time increments for display, and to convert all non-
hourly time increments to hours for storage in the database.
 The Primavera Database Administrator has the ability to define
certain settings globally such as Hours per Time Period. The Admin
PreferencesTime Periods tab will be used to specify the Hours per
Time Period settings be defined per calendar. In this way, the
specific calendar will no longer inherit the attributes of any other
calendar.
 When Hours per Time Period settings are defined per calendar,
units and durations are displayed more accurately.
 When Hours per Time Period settings are defined globally and you
set your user preferences to display units and durations in time
increments other than hours, units and durations will display
unexpected values when the Admin settings for Hours per Time
Period do not match the work hours specified in calendars
assigned to activities and resources.

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Author: Rufran C. Frago, P. Eng., PMP, CCP, PMI-RMP
 This occurs because the display reflects the conversion factor of
the Admin Preference Hours per Time Period settings, not the
hours per day defined by the activity or resource's assigned
calendar.
For example:
User Preferences, Time Units = day
Admin Preferences, Hours per Time Period = 8h/d
Activity calendar, Work hours per day = 10h/d
User-entered activity duration = 30h
Actual duration display = 3d6h
30h duration/8h per day, based on the conversion factor set in
Admin Preferences
Expected duration display = 3d
30h duration/10h per day, based on the conversion factor set in
the activity calendar
To avoid unexpected display, the Administrator should mark the
Use assigned calendar to specify the number of work hours for
each time period checkbox on the Admin Preferences, Time
Periods tab.

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Author: Rufran C. Frago, P. Eng., PMP, CCP, PMI-RMP
9.7 REFERENCE TABLE FOR DEFINING THE TIME PERIOD IN YOUR
CALENDARS
Figure 4
(Ww) * (Wo) = No of Week on X No of Week off
~/W = (~/Y)/52
~/M = (~/Y)/12
~/Y = 365/(Ww + Wo)

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Author: Rufran C. Frago, P. Eng., PMP, CCP, PMI-RMP
10.0 INDEX
“Global” calendars 4
“User” 3
ADDITIONAL READING MATERIALS 4
Admin Setting for Time Period 3
BACKGROUND INFORMATION 5
calculating predecessor activities 7
correct values 5
DEFINING THE TIME PERIOD 10
DEFINITION 3
FOOD FOR THOUGHT 4
ILLUSTRATIONS 5
INDEX 11
Inherit Holidays 5
lag calculation 4
Primavera Scheduling Tips & Tricks 01-13 (UPS) 4
PROBLEM ANALYSIS 3
REFERENCE TABLE 10
REFERENCES 4
RELATED TOOLS 3
required attributes of the Global and Project calendars 8
REQUIRED SETTINGS 5
SCHEDULING RELATIONSHIP LAG 7
SITUATION/PROBLEM 3
SOLUTION 4
TABLE OF CONTENTS 2
To avoid unexpected display 9
Users Preference Setting (UPS) issue 3