One thing to keep in mind - IMHO the Project Calendar should not describe
the total working hours of the firm. Rather, it describes the working hours
of a generic or typical resource. While companies often work 24/7
individual workers don't. And in a project's task breakdown, the work
should be decomposed down to the level of a task describing the work
performed by ONE resource, that being either a single individual worker or
several workers working as a team. So the calendar that controls its
scheduling when resources have not yet been assigned (or won't be assigned
by us such as when we don't care who a contractor actually sends to do the
work) should at least approximate the working hours of the resource most
likely to actually do the work. In other words, the Project Calendar should
descibe the hours during the day when the work being done on a single
activity by a single worker will take place.
Consider - We operate 24 hours a day and our workers work 8 hour shifts,
either day shift (Joe) 8-5, swing shift (Bill) 3-mid, or graveyard shift
(Fred) 11pm-8am. I have a task that starts Mon at 8am and requires 40 hours
of work to do. If I use the 24/7 calendar and enter that task, before
assigning resources it shows starting Mon 8am and finishing Tue at midnight.
But if I assign only Joe, which is the normal situation, as we originally
planned on - instead it's suddenly jumps out 3 days and it doesn't finish
until Fri at 5pm. That's HUGE difference between what it appeared it would
be and what it will turn out to actually be. OTOH, if we use the Standard
default calendar, we don't have that problem It would show starting at 8am
Mon and ending 5pm Fri and when we assign Joe it doesn't change. Even if we
use one of the guys on one of the other shifts I switch in the task timing
isn't so dramatic - assigning Bill will shift the task to Mon 3pm to Fri
midnight, not a dramatic difference and just what we'd expect anyway. And
if we DO assign it to to the guys on all three shifts so it is a task that
runs continuously, it will contract as we would expect - starting Mon at 8
with Joe working on it till 5, Bill coming on board at 3 joining Joe and
working until midnight, Fred coming in at 11 and joining Bill and working on
it until 8, Joe taking over again at 8am Tue and likewise Bill joining him
again Tue at 3 and ultimately finishing at midnight Tues with Joe doing a
total of 16 hours work, Bill also doing 16, and Fred doing 8. The duration
would still show 5 days because a "day" actually corresponds to a shift and
Mon 8am to Tue midnight means the task extends over 5 work shifts.
--
Steve House [MVP]
MS Project Trainer & Consultant
Visit
http://www.mvps.org/project/faqs.htm for the FAQs