Fixed Duration Question

[Anita]

I have my default task type set to fixed duration.

I have a task with say a duration of 2 days with 1 person assigned to it. If
I add another resource and ask Project to reduce the duration (using the
smart tag option) I expect it to halve the duration. Sometimes it does,
other times it doesn't. I have tried ticking the effort driven check box and
sometimes it even increases the duration! What's going on?

If I fix Duration, then why is it changing?

Thanks (Project XP user)

 

[Krish]

Anita,

When you select Fixed Duration, it means that you want Duration to
remain a constant. Even if you add more resources, the duration is not going
to change. TThis link will give you an idea of the formula MS Project uses
for scheduling.

http://office.microsoft.com/trainin...ID=RP010783911033&CTT=6&Origin=RP010783901033

Thanks,
Krish

 

[Steve House]

"Fixed Duration" does not mean the duration will never change. It controls
what happens in a very specific set of circumstances only - that is, when
you are edting a resource assignment - not adding or removing names but
changing the parameters for resources that are already assigned - and you
change the assignment percentage you want Project to recalcuate the work
estimate rather than the duration estimate or if you edit the work required
you want Project to recalculate the percentage required from the resource
rather than change the duration. Essentially if you're not explicitly or
effectively editing a) percent assignment for resources already on the task,
or b) the work estimated to be required of the resources already assigned to
the task, it has no effect.

The 'Prime Directive' is Work = Duration * Units and that identity cannot
ever be violated. When you edit a resource assignment you change your
choice of any one of those three parameters. The task type setting
determines which of the remaining two terms Project will hold constant so
the remaining one gets recalculated.

 

[Mike Glen]

Hi Anita,

Welcome to this Microsoft Project newsgroup

You might like to have a look at my series on Microsoft Project in the
TechTrax ezine, particularly #10 on multiple resources, at this site:
http://tinyurl.com/2xbhc or this:
http://pubs.logicalexpressions.com/Pub0009/LPMFrame.asp?CMD=ArticleSearch&AUTH=23
(Perhaps you'd care to rate the article before leaving the site,
Thanks.)

FAQs, companion products and other useful Project information can be seen at
this web address: <http://www.mvps.org/project/>

Hope this helps - please let us know how you get on

Mike Glen
MS Project MVP