Sometimes I feel it's convenient to think of the predecessor as meaning
the "controlling task" while the successor is the "controlled task."
Predecessor and successor don't always mean "the first task and then the
second." In your case, the predecessor is actually Task B since it is
what controls the scheduling of Task A. I'd join them Start-Finish
where B's start is the predecessor to A's finish as the successor.
Yes, I've got you.
Here is what I have: The Start of Task A is dependent on the start of
Task
B. For this type of task I am normally given the date that Task B will
start
(It's beyond our control). Also, for these tasks, Task A must start a
certain
amount of time prior to the start of task B, we will say 24 hours.
Task A and
the resource for task A is a 24 hour calendar. Task B and it's
resource is a
Standard calendar. So to set the start of task A I assign Task B as
Pred, SS,
-24 hours (Or -24eh). Since Task A and it's resource is a 24 hour
calendar I
don't understand why on the other machine it doesn't come out that
Task A
doesn't start 24 hours in advance of the start of task B, when on my
machine
it works exactly like my mind thinks it should. So anyway, back to the
lead
time using -eh, it is only setting the start time of task A, the
elapsed
duration matches up to the task and resource calendar of Task A so I
get the
correct amount of work.
Since I am using 24 hour task and reource calendar I still can't
figure out
why it works at my desk but not the other one. But that's why I have
settled
in on just using the eh as lead time.
:
However using EH as your basic unit of scheduling ignores resource
availability, the differences between working time and non-working
time
through the day, etc. IMHO using that approach virtually guarantees
you end
up with an unworkable bogus schedule that has no relation to what is
realistically attainable. If task requires a painter paint 400
square feet
of wall and the rate he can apply paint is 10 square feet per hour,
he has
to do 40 man-hours of work, period, end of story. The number of
days on the
planner calendar on the wall that it takes him to do that depends on
the
number of hours a day that he is physically present and able to
work. His
working time calendar is crucial to the schedule - the elapsed
time - number
of sunrises and sunsets between when he starts and when he ends - is
totally
irrelevant to how long it will take him to do it. It'll take 40
hours of
working time to complete the task regardless of whether he works
straight
through from Monday morning till early Wednesday morning or spends
an hour a
day for 40 days. If the objective is to be able to tell the carpet
guy when
the painter will be finished and out of the room so he can start to
lay the
carpet, the painter's working time calendar and the amount of work
painting
requires are the two values that actually give you that information.
--
Steve House [Project MVP]
MS Project Trainer & Consultant
Visit
http://www.mvps.org/project/faqs.htm for the FAQs
Thanks Steve. I have resolved myself to using eh and have given up
worrying
about why the machines are showing different things. I have
several
different
task calendars and resource calendars and there is just a setting
somewhere
that needs to be changed and I can't find it.
EH ALWAYS works, no matter the circumstance, it only makes
sense...so
that's
what I am going with.
As usual, you guys can set me straight. Thanks
:
As pointed out, unless you're using elapsed time ("eh") 48 hours
IS 6
days
so perhaps the difference is simply a matter of one machine being
set to
show durations in days while the other is set to show durations
in hours.
Lag times and lead times are normally based on "duration hours"
ie,
working
time hours as defined in the Project Calendar, and any embedded
non-working
time doesn't count in the numbers, exactly the same way task
durations
are
reckoned.
--
Steve House [Project MVP]
MS Project Trainer & Consultant
Visit
http://www.mvps.org/project/faqs.htm for the FAQs
I am sure that this has to be a set up problem but let me say
what I am
running into.
On my machine in Project 2002, I can schedule a task then make
it a
predecessor another task that needs to occur 48 hours ahead,
using
"pred-ss-
-48h". It works fine. Just like I want it to. But, on another
computer
it
schedules it much differently. It looks like maybe it takes
that 48
hours
and
makes it 6 days and disregard the SS relationship and schedules
it from
the
finish. The calenadars appear to be the same and the hours in a
day are
both
set to 8.
Anybody have any notion about what is going on?
