Adding work countour changes work time..why?

[TraceyH]

I have created a task as 'fixed duration' and not 'effort driven'. Resource
leveling is 'manual'. I assign individual resources at 30%. The default flat
countour is applied and the calculation is fine. But whenever I go back to
the task and apply a different contour to a resource (tried back load and
late peak) the effort/work changes. I have not created resource calendars or
modified the standard calendar, though I do not have the have the standard
calendar assigned to a task...i can't understand why Project is recalculating

 

[JulieS]

Hello Tracey,

When you apply a work contour, Project modifies the assignment units
over time on the task. In order to maintain the mathematical
relationship between work, duration, and assignment units, when you
alter one something else has to change. Because you have set the
task as fixed duration and are altering assignment units through
contouring, Project must change work to maintain the formula:
Word = Duration * Assignment units.

Try adding the Peak Units field to the right side of the Task Usage
view. You'll see with contours other than flat, the peak units
varies day by day.

I hope this helps. Let us know how you get along.

Julie
Project MVP

Visit http://project.mvps.org/ for the FAQs and additional
information about Microsoft Project

 

[José Miguel Piñeres]

Hello TraceyH,

Welcome to this Microsoft Project General Questions newsgroup.

Allow me to clarify a couple of concepts that might help you to better
understand the situation:
1.- When you chose the "Fixed Duration" type task and unchecked the Effort
driven box, you actually told Project that the only thing that matters in
that task is its duration, regardless of the amount of resources you add or
remove. In other words, duration cannot be modified. Therefore, Project
assigned the amount of work to be performed accordingly (work = duration *
units), taking in account the resource's calendar.
2.- When you apply a work contour, you do it at the assignment level, not at
the task level. A "Flat" contour means that the work will spread evenly
through the duration of the task. If you apply a "back load" contour, then
you are telling Project that most of the work is to be done at the end of the
assignment and, very little work at the beginning (respecting the resource's
calendar). Therefore, since you are not allowing duration to be modified,
Project hast to adjust the amount of work of the task in order to fulfill the
new work requirements (contour).

If the task type would have been "Fixed units", Effort driven, then Project
would have adjusted the task's duration.

I hope this helps. Please, let us know how you get along with it.

--
If this answer has been of help, please consider rating it.

José Miguel Piñeres
MCITP | MCT
San José, Costa Rica
http://projectpedia.blogspot.com

 

[vanita]

Hi

The gradient and shape of work contours is predefined in MSP. So if you
apply any other contour except Flat and based on the prespecified contour
details, work hrs perday have to exceed the hours per day data as given in
Tools > Options > Calendar the software has to increase the duration. If you
make the task 'Fixed Duration' it has no option but to reduce the total hrs
of that resource on that activity.

That is why generally in small duration activities it would be difficult to
apply a work contour. You may change the work assignment in different cells
manually after making the task 'Fixed Duration'

I hope it helps.
Vanita