Working with Shifts

[Dave]

Does anyone know how to work with shifts in MS Project
2002? I need to schedule jobs over a 24 days and when I
allocate to many resources it seems to do the math wrong
on more than 3 people if they are working a swing shift.

Thanks,
Dave

 

[mmaxwell]

I work in manufacturing and I'm having trouble with shift work too...actually I logged on to see if any new posts have been added on the subject.

I think the problem that you are seeing is that when you assign 3 shifts (resources) to a task MS Project requires that ALL resources work on that task. For instance, I assigned 3 shifts (24 man hours) to a task that only required 6 man hours to complete. I wanted all 3 shifts to be "available" to work because I wasn't sure which one would actually do the work when it was time. What I have observed, and would like a solution too is this, Project assigned each shift 1/3 of the work...or 2 hours. 1st shift worked on the task from 8-10 am then did nothing. 2nd shift worked from 4-6 pm and then did nothing. 3rd shift worked from midnight to 2 am then did nothing. A task that should have taken 3/4 of a single shift had a duration of one full day

The only way around the problem that I have found is to assign only one resource to the task. I used the resource "Tech" and assigned him at 300% (or 3 people) and left the working hours set at the default. It is NOT perfect but it is a close approximation. If anyone else has any idea how to accurately handle resources that work shifts, please let us know.

 

[Steve House]

You're on the right track with your first approach but IMHO went wrong with
a fundamental error regarding the nature of a task in a project plan. A
task is a discrete, measurable package of physical work that has a definite
observable start and ending time. It's duration is the actual amount of
time between when it starts and ends. Where I think you (and many others,
you're not alone) went wrong is you used "duration" to mean the limits
between when it *could* take place and not a prediction of when it *will*
take place. If I have a task that will take one day of work that must be
done sometime between Monday and Friday of next week, it is a one-day
duration task with a Friday deadline, NOT a 5-day task with a MFNLT
constraint of Friday. You went on to say you did this because you didn't
know which shift would be available to do it. The problem with that is the
function of the project manager is to *designate* when it will be done - you
look at when the predecessor task will be done, let's say it finishes at 2pm
Tuesday and thus the task in question can start anytime after that. You go
to the swing shift foreman and tell him to assign someone to the task
Tuesday evening. Note he doesn't tell you when he's scheduled someone, you
tell him when he needs to schedule them.

So in your example, your task is 6 hours duration and has one resource
assigned 100% (NOT 300%, that screws up your work estimates and budget by
showing the task requiring and costing 18 man-hours work when it should only
be 6). If that resource is a day shift worker the task will be scheduled
duration the day. If that works well from the project objectives, fine. If
the predecessor finished at 2pm the previous day and you need the task in
question really to begin asap, then assign it to a swing resource instead
and it will move up closer to when the predecessor ended. Then you go to
the foreman/manager, whoever is the person that has the functional authority
over the workers and tell them they need to assign a worker to do the work
starting at such and such a time from whichever shift that you've decided is
best for the project schedule.


--
Steve House [MVP]
MS Project Trainer/Consultant
Visit http://www.mvps.org/project/faqs.htm for the FAQs

I work in manufacturing and I'm having trouble with shift work

too...actually I logged on to see if any new posts have been added on the
subject.

I think the problem that you are seeing is that when you assign 3 shifts

(resources) to a task MS Project requires that ALL resources work on that
task. For instance, I assigned 3 shifts (24 man hours) to a task that only
required 6 man hours to complete. I wanted all 3 shifts to be "available" to
work because I wasn't sure which one would actually do the work when it was
time. What I have observed, and would like a solution too is this, Project
assigned each shift 1/3 of the work...or 2 hours. 1st shift worked on the
task from 8-10 am then did nothing. 2nd shift worked from 4-6 pm and then
did nothing. 3rd shift worked from midnight to 2 am then did nothing. A task
that should have taken 3/4 of a single shift had a duration of one full day.

The only way around the problem that I have found is to assign only one

resource to the task. I used the resource "Tech" and assigned him at 300%
(or 3 people) and left the working hours set at the default. It is NOT
perfect but it is a close approximation. If anyone else has any idea how to
accurately handle resources that work shifts, please let us know.

 

[Steve House]

Actually Project does not assume that a task must be complete before the
next task in the schedule can begin. Tasks can be sequential or parallel.
Even when sequential, there can be an overlap (lead time) where the
follow-on task begins before the first task ends. An example I use in may
classes of that is the hiring process - we must review resumes before
calling candidates in for interviews but we don't have to get through all
the resumes in the stack before starting to interview some of the likely
candidates - the interviewer can start on the first candidates while the
reviewer is completing the resume screening.

The problem is not with shifts per se. Hard to say just what it is without
seeing the plan. But remember that resource leveling does one and only one
thing - it delays work. It never adjusts assignments, levels, or the amount
of work a resource will do on the task, all it can do is shift a task (or a
resource's designated portion of a task) into the future to a time where its
assigned resource, overbooked at the originally scheduled time, is otherwise
free to work. If Joe is booked for 8 hours work on Monday waxing widgets
and also on Monday for 8 hours work polishing fids, he's overallocated.
Leveling will shift the lower priority task of the two over to the next day
that the resource is working and isn't already scheduled on something with
higher priority. That's all it does. It's not able to reason out "Joe can't
work 8 on Monday but he can work 6 and Fred is available to pick up the
other 2." If Joe is assigned 8 man-hours, he must do all 8 man-hours -
period. If there are other viable distributions of the work among the
resources, leveling isn't aware of it and you must adjust it manually.
........

If a task takes 4 man hours and I'm working a 3 shift operation with 2 people
per shift the duration should be 4 manhours / 2 men x 8 hours = 0.25 days.

..............
Not necessarily. 2 people per shift doesn't mean that both are qualified to
do the work or that both are free. It could just as easily be 1 man working
for 4 hours for a duration of .5 day. Or one man on day shift working 2
hours and one on swing shift for two hours in sequence for .5 day. Or we
work the task from 3pm to 5 pm, one guy from day and one guy from swing
working together for a .25 day duration.


--
Steve House [MVP]
MS Project Trainer/Consultant
Visit http://www.mvps.org/project/faqs.htm for the FAQs

Steve

Thanks for your detailed response. Some things were probably not clear in

my reponse to the previous post. I work in a manufacturing plant where we
can (but do not like to) work 3 shifts per day. I have developed a
production schedule based on a combined "best guess" of all the parties
involved. We are a job shop and rarely make more than a handful of any given
part, so historical data as to how long tasks should take is not always
available. As with any plan, things go wrong so when I schedule a project to
start on Monday morning at 8 and by Monday at noon things have shifted
because a peice of equipment failed, I can't afford to "go back to the
drawing board" and reassign or adjust recsources to cover gaps in shifts.

I think the fundemental issue is that MS Project is focused on the task

completion, meaning that given the WBS, one task must be completed before
moving on to the next. If resources were used in a similar way...resource 1
(1st shift) would use all of its available manhours before allowing resource
2 (2nd shift) to start work. The issue that I found assigning more than one
resource was that if the task took less than the manhours assigned to
resource 1 (1st shift), Project would split the total manhours for the task
evenly among the resources. As I mentioned earlier, I can't take the time to
adjust the schedule by the hour. If 3 shifts are available to do the work I
would like have the resources assigned according to their respective
calendars and have them be used in a logical manner(the way people work). If
a task takes 4 man hours and I'm working a 3 shift operation with 2 people
per shift the duration should be 4 manhours / 2 men x 8 hours = 0.25 days. I
thought that the leveling function would address things like this but is
seems to make it worse. Is there a 3rd party leveling tool available?It may
be that I'm using the wrong tool for manufacturing although I have seen
other posts with similar issues regarding shift work in the service
industry.