Necessary but insufficient resource

[Leslie Harmer]

Hello. I would like to schedule a series of tasks that
each require the use of a certain machine. The machine is
only available at certain times. Only one task can use
the machine at a time. Thus, it may not matter how many
people I assign to a task, because progress can only be
made when the machine is available. How do I do this in
MS Project? (I am using MS Project Standard 2002.)

Thanks!

 

[Trevor Rabey]

this is the perfect problem for MSP (actually at the core of what it is
for). make the machine a material resource rather than a work resource then
assign it to the various tasks along with the work resources. edit the
calendar for the machine to show its availability, then level. all tasks
will get delayed to remove overallocation of the machine. if you don't like
the sequence produced by the levelling you can tweak it by adjusting the
priority of the tasks and then level by priority (see tools, resource
levelling) hope this all helps and makes sense.

 

[JulieD]

hi Trevor

don't have project 2002 loaded on this machine - but is the tick box -
"leveling can adjust individual assignments on tasks" still on the leveling
screen? - as to achieve what the OP wants they would have to ensure that
this box was unticked wouldn't they?

cheers
Julie

 

[Leslie Harmer]

Thank you, Trevor. It does make sense. I have not tried
it yet, but it seems perfectly clear. Unless I post
again, please assumet that it worked. Thanks again!

 

[Steve House]

Trevor, I think you got it backwards. The machine is a work resource,
not a material resource. Materials don't have calendars or availability
nor participate in leveling but work resources do. Clearing the
checkbox "Leveling can adjust individual assignments" will insure that
the machine and the operator will stay together.

 

[Leslie Harmer]

I see the problem. When you classify a resource
as "material," MS Project greys out the "working times"
tab so that you cannot set working times.

When I assign the machine as a resource, all it does is
make the work get done in fewer houss. It seems to think
that the machine is another helping hand, not a limiting
factor.

 

[Leslie Harmer]

Hello. I've looked at the replies on this, for which I am
grateful. However, I've concluded tentatively that it
can't be done. If you add a machine as a resource, MS
Project simply uses it as another pair of hands to do the
work, so the work gets done faster. Project uses
resources to get work done. What I need is a way to
prevent work from getting done, unless a certain resource
is available. Does anyone have either a new answer or
some re-explanation of a point already made here? Thanks.

 

[Steve House]

Make the task non-effort driven before you add the machine resource or
assign the machine and its operator in *one* operation. The reduction
in duration you're seeing is the behavior of effort driven tasks when
adding resources after the initial assignment.

 

[Trevor Rabey]

not entirely backwards.
but yes, of course the machine is a work resource because it will have a
calendar and get levelled.
and yes, turn effort driven off at least briefly while making the
assignments or else have to re-input the duration.
..

 

[Trevor Rabey]

sorry, but your tentative conclusion is incorrect. MSP is used for this all
the time. we just had a minor difference of opinion about resource type, now
resolved.
turn effort driven off for the task and make the task "fixed duration" and
then it won't make the task go faster.
make sure to uncheck the .."adjust individual assignments" thingy.

 

[Leslie Harmer]

Trevor, I tried your suggestion and it worked. Ominously,
I tried setting up a separate little experiment, outside
my actual project, to further test your suggestion, and
there it gave strange results. I am relucant to explore
that in this forum, which I assume is devoted to actual
situations. The point is, my project works. Thank you.>---
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