Task types in MS Project 2007 does not act as in program help 1

[fkr1972]

Task types in MS Project 2007 does not act as in program help.

Case one:

For a fixed units task of 4 days duration and 8 hours/day using only one work resource R1 at 50% units to perform work of 16 hours, if I add a work resource R2 to this task at 50% units, program recalculates work to 32 hours [(50% + 50%) x 4days x 8h/d] and suggests another option by a temporary indicator that, to fix work and recalculate duration.

In program help it is mentioned in a table clearly (In a, Fixed units task, If you revise units, Duration is recalculated).

Case two:

For a fixed units task of 4 days duration and 8 hours/day using only one work resource R1 at 50% units to perform work of 16 hours, if I increase duration to 6 days, program fixes unit at 4 days, recalculates work to 24 [50% x 6days x 8h/d] and suggests another option by a temporary indicator that, to fix work and recalculate units.

In program help it is mentioned in a table clearly (In a, Fixed work task, If you revise duration, Units are recalculated).

I am confused.
What is my mistake?
Please lead me?

 

[JulieInMaine]

Hello fkr1972,

You're missing a key piece -- whether the task is effort driven or not. Effort driven scheduling modifies how Project deals with the addition (or subtraction) of named resources.

In case one -
My guess is that the task is not effort driven. By adding an additional resource to an effort driven task, you increase the total amount of work. There is no need to recalculate duration as work increased to keep the Work Duration and Units math stable.

If the task was effort driven, adding an additional resource would drop duration as the total work would still be 16 hours, now performed by two resources.

In Case Two:
Is the task Fixed Units or Fixed work? You state:
For a fixed units task of 4 days duration and 8 hours/day using only one work resource R1 at 50% units to perform work of 16 hours

If the task is fixed units, it behaved as expected - you increased duration, Project increased Work.

The math does not recalculate after the fact -- if the task was fixed units and you changed duration - work is affected.

The information in help applies to changing one of the 3 values - work, duration, or units after the initial assignment and without adding more resources. If you are adding more named resources, then the issue first is whether the task is effort driven or not.

I hope this helps.

Julie

 

[fkr1972]

Dear Julie

Thank you for response.

I am sorry I missed to mention that,:
1- case 1 is not effort driven.
2- case 2 is fixed work.

Case 1

You are right. You agree with me about the task behavior. This behavior is not as mentioned in program help. This is my case.

Case 2

It is a fixed work task and not effort driven which changes work when I change the duration; conflicting the rule in program help.

I am sharing my MS project knowledge and I am keen to give everything in compliance with program help.
These two cases are not in compliance with program help; at least for me up to now.

I attach a example file for the two cases.

 

[JulieInMaine]

I understand you want to align what you are seeing in Program help -- but the help you are quoting is not the full story. If you are adding resources - the first issue to be addressed is whether the task is effort driven.

Adding resources to a non-effort driven task simply increases the amount of work.

So add a new resource to:

a Fixed Units non-effort driven task - work increases: units for all ready assigned resource and duration are unchanged.

a Fixed Duration non-effort driven task - work increases: units for all ready assigned resources and duration and unchanged.

Fixed Work tasks cannot be non-effort driven so I don't know where you come up with the statement:

It is a fixed work task and not effort driven

To finish out:

Add resources to:

a Fixed Unit effort-driven task - total work for the task remains stable, Duration drops, assignment units for all ready assigned resources stays stable

a Fixed Duration effort-driven task - total work for the task remains stable, duration stays the same (it is fixed), assignment units drop.

a Fixed Work effort-driven task - total work for the task remains stable, Duration drops, assignment units for all ready assigned resources stays stable

In your attached file for Case 2 - neither task is Fixed work -- both are Fixed Units.

Split your screen to show the task form in the lower pane and you can easily see (and change) effort driven, and task type. As a note - if you are using Project 2010, you will NOT see the assignment units change in the task form -- you need to show the Task Usage view and add "Peak" to the timescaled portion of the view to see the change in assignment units.

For further information on the "whys" of the change in Project 2010 see:

http://blogs.msdn.com/b/project/archive/2010/04/29/assignment-units-in-project-2010.aspx

Working with resources in Project is likely the most complex thing to teach (I've been teaching Project since 1992), so you really need to experiment with all possible combinations -- understand exactly what Project does and why and under what circumstances. Reading help likely won't be enough.


I hope this helps.

 

[fkr1972]

Dear Julie

Thank you very much for the information.

It really helped me.

 

[JulieInMaine]

You are most welcome and thank you for the feedback. Feel free to visit again as you have more questions about Project.

Julie