In this case I think you've misunderstood what "% assignment" really means.
If someone works an 8 hour day and I assign them to a task at 50%, that does
NOT mean I expect them to work on the task for 4 hours. The assignment
percentage is actually a RATE measure that describes the way the resource
efforts converts time spent into work accomplished. If you have a task that
has 8 hour's duration and someone is assigned to it at 50%, the resource is
still actively working on it for the full 8 hours but because of some other
simultaneous demands on his time, he gets the amount of work done that would
have taken him 4 hours if he could have devoted his undivided attention to
it.
Assume the default calendar and a 1 day (8 hour) duration task. Assign the
resource to it 100% and he spends 8 hours generating 8 man-hours of work.
Assign him to it 50% and he spends 8 hours to generate 4 man-hours of work.
Assign him to it 25% and he spends 8 hours to generate 2 man-hours of work.
But in all cases the amount of time he spends on the task is 8 hours, with
it starting at 8am and ending at 5pm.
You usually would expect a resource to devote his full attention to the task
at hand. If you have a task that requires 2 hours of effort, make it a
2-hour duration task and book the resource 100%, not an 8-hour duration task
with the resource booked on it 25%.
The program doesn't assume both tasks start at 8am. It actually doesn't
assume anything. The project calendar determines the initial start time of
tasks since work can only take place when people are there to do it and that
information comes from the project calendar. Those tasks start at 8am
because you told Project that's when work can start. If there were infinite
resources, all resources could do any task, and no physical dependencies,
all the tasks could begin simultaneously at the first possible working
moment in the calendar after the project kicks off. It defaults to
simultaneous rather than sequential because the 'prime directive' is to get
the entire project done ASAP. The first reason they can't all happen at once
is that some tasks are physically dependent on the scheduling of
predecessors, so their timing is modified by dependency links. The second
determiner of the task's start is the availability of the specific resources
who are able to do the work - a task has to wait until a person with the
required skills comes to work, if he's on vacation the task has to wait.
Resource calendars are the source of that information. And the third
determiner is that resources can't be in two places at once so the final
schedule is determined by delaying some tasks through resource leveling to
resolve overallocations.
In your example, both tasks COULD start at 8am. You didn't specify that you
have to inspect the steelwork and brickwork in any particular order so from
that standpoint they could both start at 8. If you had two inspectors they
could both start at 8. With one inspector they will initially be
overallocated but leveling will sequence them. Or could if they happen at
the same time, Fred doing both at once, make each of them 6 hours duration
and assign him 50% to each.
If you don't want meetings to start at 8am, specify the start time as part
of your entry for the task.
--
Steve House [Project MVP]
MS Project Trainer & Consultant
Visit
http://project.mvps.org/faqs.htm for the FAQs
Rai said:
Firstly let me say that this resource is several hundred percent better
than
the programs help files, and thankyou all for responding.
This seems to be an over zealous way of controlling resources.
IMHO the majority of resource managers would book Fred in to inspect the
Steelwork, at one point on Thursday, and then inspect the Brickwork that
afternoon. If the 2 tasks absorb a total of 6 hours...the only way that he
can be overallocated is that the program assumes they both occur at 8 am.
I dont get the % thing, particularly when he has 6 hours of work to do in
an
8 hour day...???? If the % doesn't relate to the amount of time he has
booked, versus the amount of work to do, then what does it represent?? I
would have thought that the default setting would be that the tasks occur
sequentially instead of simultaneously. Can I change 'projects' way of
thinking?? I can't allocate Fred to an afternoon meeting without
overallocation as there is no function other than multiple calendars
(messy)
The program is meant to make life easy......isn't it?
The further i get into programming this project, the more over allocations
I
am getting because all meeting start at 8 ??
I am really getting frustrated at having to tell project that it's
assumptions aren't what happen in the real world.
Hope you can help.....:-(
Steve House said:
Don't think in terms of total hours. "Overallocation" does not refer to
totals - it is an instantaneous thing. If a resource is on two tasks,
each
at 100%, and those two tasks overlap for even one minute, no matter how
long
each task may last, the resource is overallocated. For example, I have a
sample file with a situation where a resource works 8 to 5 and has an
allowed maximum allocation of 100%, 8 hours of work during an 8 hour day.
On a certain day, she is booked on two tasks, each 100%. One task is 2
hours long, the other is 4 hours, for a total of 6 hours work she's
scheduled to do that day. Now you might think that she's only booked for
75%, 6 divided by 8 is 0.75. But Project says she's overallocated and
shows
a peak allocation of 200%. Why? There's a couple of crucial pieces of
information I haven't mentioned yet. Task A starts at 8am and ends at
10am.
Task B starts at 8am and ends at 12 noon. The overallocation occurs
because
during the 2 hours of time between 8am and 10am, she is required to
perform
a total of 4 man-hours of work, 2 hours of each task and that's
physically
impossible. Resource leveling resolves the overallocation by moving one
of
those tasks so they happen sequentially rather than simultaneously.
--
Steve House [Project MVP]
MS Project Trainer & Consultant
Visit
http://project.mvps.org/faqs.htm for the FAQs
Rai said:
I have two situations where resources are shown to be overallocated on
the
resources graph, and are highlighted in red in all other views
BUT...they
are
allocated for 8 hours of an 8 hour day at 100%. Resources have 8 hours
available on their calendar, with no other commitments.
In one of the situations, the 'work' column has turned blue.....and I
can't
find that mentioned in any help files...
If I reduce the resource to 5 hours total for the day, the
overallocation
is
solved but the second of the two tasks turns blue instead.
