Time [anchor]units [/anchor]are the intervals on which activities and other objects are based. For example, an activity’s duration may span one day or any whole unit increment thereof. The schedule time unit may be set to a unit as small as minutes or as large as years. The time unit may not differ from activity to activity—once set, it applies to all objects within the schedule. Durations, dates, and float values are all calculated according to the schedule’s time unit.
Small time units—like minutes and hours—are useful for projects with short durations or for showing an extremely high level of detail. Large time units—like months and years—are useful for projects with long durations or for showing an extremely broad level of detail. If the schedule is blank (i.e. no activities or other objects have been drawn), the time unit can be changed to a higher or smaller unit. The calendar dates and project dates will automatically update to a reasonable range. However, once an object has been placed on the canvas, the time unit may be changed only to a smaller unit. The calendar dates and project dates will remain fixed. This restriction is enforced because converting to a larger time unit would involve either rounding or truncation and would potentially result in changes to dates and durations (which would result in altered gaps, floats, drifts, etc.).
NOTE: Small time units can only be used if the duration of the project is reasonably short or if the size of the canvas is sufficiently large. Otherwise, the width of a time unit would be less than the width of a pixel on screen, and input from the mouse would no longer translate accurately on the canvas.
NOTE: When converting to time units smaller than days, some dates may appear to change; however, they are only realigning – all float calculations and values will remain constant. This is because with days, weeks, half-months, months, quarters, or years, dates are aligned to the end of the prior unit, whereas with hours, quarter hours, and minutes, dates are aligned to the start of the next unit. For example, a three-day activity that starts on May 1st will end on May 3rd at 11:59 pm. If converted to hours, however, the same three-day activity will now end on May 4th at 12:00 am. This is done to align with other applications as well as user expectations.
When converting plans from a higher time unit to a lower time unit, or when exporting a plan that is in any time unit other than days, resource assignments may not be accurate. For example if 48 widgets are assigned per day and the time unit is changed to hours, then 48 widgets would be assigned per hour instead of 2 widgets being assigned per hour. The following approaches may be taken to correct the outcome: 1) wait to resource load the schedule until the file is converted or exported; 2) reassign every resource to every activity after converting or exporting to correct the values; or 3) delete the resource assignments prior to converting or exporting and start with a clean resource-assignment slate, but with resources defined.
When working with time units of hours or smaller, NetPoint does not support “daily calendars” or “shifts”. For example, if a schedule in days is converted to hours, a working day is converted to 24 working hours. Similarly, a 1-day gap is converted to a 24 hour gap. As a result, hours, quarter-hours, and minutes are only recommended for schedules without non-work periods.