So you’ve just obtained access to Primavera P6 Professional and are eager to commence scheduling your first project. However, before you begin work, it is important to set up a few options related to inputting activities and their associated resources.
This article takes a close look at just one of the user preferences you may wish to consider when you first gain access to a Primavera P6 Professional system – the Time Units tab.
First among user preferences that you should set are the Time Units that Primavera will use for activities and their resources. The Time Units settings control the way Primavera P6 displays and manages values of activity durations and resource assignments. Let’s take a closer look.
This will get Primavera P6 set up for the entry of activities, activity durations, and the associated resources. When you select Edit | User Preferences from the drop down menu at the top of the screen and then select the very first User Preference option at the top of the User Preferences dialog, you will see the options shown in Figure 1.
Figure 1
Selecting the drop down menu under either Units Format or Durations Format will bring up the list of Time Units available in Primavera P6, see Figure 2. The Units Format Unit of Time options available as displayed in Figure 2 are the following: Hour, Day, Week, Month, and Year. The most common option for this is ‘Hour’ because we typically think about labor resources working on an activity for some number of hours.
Figure 2
P6 Labor Resources
Setting the appropriate Units Format Unit of Time will be helpful to you when assigning resources. In figure 3 you can see the Budgeted Units for the Foreman as 760 hours because we selected the ‘Hour’ option in the Units Format – Units of Time field.
Figure 3
P6 Activity Durations
The Durations Format – Unit of Time field controls how activity durations are displayed. Typically this is set to Day in the User Preferences as it is common to think of activity length in terms of days. In some situations however, such as planning a short term outage at a power plant, it may be preferable to set the activity duration to display in hours, as some tasks may be very short in duration.
P6 Units Time/Format
The Units Time/Format for activities can be specified using a percentage or hours per day. Refer to either one of the first two figures to see the Units Time/Format options. You can enter the resource effort as either a percentage or as hours per day. If percentage is selected then a resource working for half the day per day would be displayed at 50%. This option could be ambiguous if you are using calendars that have something other than 8 working hours per day – 50% could be 4 hours of an 8 hour day or 5 hours if using a ten hour day calendar. Wouldn’t it be clearer to say the resource is working on an activity for 4-hours per day? For the purposes of our example let us say the work week is five days and eight hours per day. Thus, specifying the labor resource at 4-hours per day on an eight hour schedule we know the number of hours the labor resource worked and can easily compute the work percentage of 50%.
Summary
Properly setting the user preferences is important to creating a schedule that supports the general guidelines that you may be working with and can also support projects having unusually short; or unusually long durations. Primavera P6 gives the scheduler great leeway in the units used to describe labor resources and activity durations.
Simply put, if you think of activity durations in terms of hours, use the Hour setting in the Duration Format – Unit of Time field, if you think in terms of days, use the Day setting and if you think of activities in terms of weeks in length, then set the Week setting.
Finally you set the Units/Time Format, either as a percentage or a unit per duration. The clearest format is the units per duration, such as 4-hours per day working on an eight hour per day five day per week work calendar. Closely related to the Units/Time Format is the associated calendar work week. You can specify a five day eight hour per day work week or a four day ten hour per day work week. Calendar settings will be discussed in a future article.