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Relationship between Duration, Work, and Start and Finish dates RRS feed

  • Question

  • I'm having a few issues with MSProject Standard 2010 (v 13.0.6112.5000, 32-bit). I have spent some time on the internet looking for solutions, but unfortunately I haven't been able to find anything of use. Perhaps it is the keywords that I am using as most of the search results I am finding are for issues completely unrelated to what I am having. I would be very appreciative if anyone could share some advice on the following issues that I am having

    Question 1. Calendar's. I'm drafting up a schedule for a small project which requires resources working 8 hour days Monday - Friday (Office), 10 hour days Monday - Friday (Site) and 24 hour days Monday - Sunday (Commissioning). I have set up these calendars, I have assigned the appropriate calendar to each resource, I have tried assigning the appropriate calendar to each task (using Task Calendar - is this redundant if I have assigned a resource?) and I have assigned the correct resource to each task (I am splitting tasks to keep one resource to each task to avoid further complication). All of the "Durations" shown on the Gantt chart keep relating back to the Standard calendar that is set up in File > Options > Schedule when I modify the Start and Finish dates. Can I get this to display the true duration, e.g. 8 hours work could be 1 day or 1/3 day depending on the resource (assuming 100% effort)? Another observation - the Start and Finish dates don't even correspond to the bar on the Gantt chart in some cases!

    Question 2. Duration/Work relationship. This flows on from my last point. I have used the "Type" field to set tasks to Fixed Duration and Fixed Work (I haven't been using Fixed Units). If I'm performing a task I like to use the amount of work required to determine the duration of the job, however for other resources I like to allocate both a duration and amount of work, as the resource is not 100% at my disposal. An example of this would be a document review. Although it might be two hours work and I have assigned the task on the Site calendar (10 hrs/day @ 100% utilised), this will often tend to take longer than a week to get back to me and so I need to allocate a duration for scheduling purposes and a work for costing purposes. If I play around with the Resource effort (by changing the [x%] after the resources name in the Resource field) I can some times get this to work, but the reality is it would be a two hour block of time spent at some stage during a weeks period (as an example) rather than 24 minutes per day for five days (what I am actually factoring in). How do I go about approaching this? Should I be setting predecessor/successor relationships rather than a duration?

    Question 3. Start/Stop/Start tasks. To try and utilise my resources better Project often splits a single task up to Start, Stop, Start, Stop, Start etc. etc. Is there an option to force a task to be done completely with no interruption? Some of my tasks might only be a days work and it would make sense to allocate a full day for this task rather than an hour here, an hour there, etc. etc. Furthermore if the schedule shows the task starting and stopping multiple times it might actually increase the amount of work (in reality, if I worked to the schedule) due to the time it takes starting up a task again. Any advice here? Side note - I would rather leave time un-utilised than this Start/Stop/Start business as I have other work I could be doing in this time.

    Question 4. Task hierarchy. I've ended up giving up on the Auto scheduler a lot here because I can't seem to set up a top - down hierachy in my schedule without forcing constraints that aren't actually constraints. For example I have a work scope, a budget and a schedule (yes I'm scheduling doing the schedule) in my schedule which all have to go through a draft, review, revise, approve, issue sequence. Due to right clicking on conflicts and rescheduling (auto schedule) the tasks are now shown in an illogical order, e.g. complete the document drafts in one order but then revise them in a different order, to the extent where its actually creating a bottleneck on subsequent tasks. The only way I have been able to work around this is by then forcing the tasks to a Manual Schedule, as the moment I try playing around with Start/Finish constraints on Auto Schedule it starts pushing out the schedule and then when I delete the constraints the schedule doesn't "refresh" back to reduce the critical path. Is there some kind of flush function that will delete all Start and Finish dates that haven't been manually scheduled or constrained, and then re-populate all of the dates? That would be really handy.

    • Moved by keith.lin Wednesday, March 6, 2013 7:38 AM It is all about Project Standard, move to Project Standard and Professional forum
    Tuesday, March 5, 2013 11:46 PM

All replies

  • Hi,

    Taking each part in turn:

    Question 1. Calendar's. I'm drafting up a schedule for a small project which requires resources working 8 hour days Monday - Friday (Office), 10 hour days Monday - Friday (Site) and 24 hour days Monday - Sunday (Commissioning). I have set up these calendars, I have assigned the appropriate calendar to each resource, I have tried assigning the appropriate calendar to each task (using Task Calendar - is this redundant if I have assigned a resource?) and I have assigned the correct resource to each task (I am splitting tasks to keep one resource to each task to avoid further complication).

    [Julie] No reason to assign the resource calendars to the tasks as well.  If you have assigned the correct base calendars to the resources, the resource calendars will drive the task schedule. 

    All of the "Durations" shown on the Gantt chart keep relating back to the Standard calendar that is set up in File > Options > Schedule when I modify the Start and Finish dates. Can I get this to display the true duration, e.g. 8 hours work could be 1 day or 1/3 day depending on the resource (assuming 100% effort)? Another observation - the Start and Finish dates don't even correspond to the bar on the Gantt chart in some cases!

    [Julie] The settings in Options > Schedule define the definition of "day" and "week" for the entire project.  You cannot define different duration measures in one project file.  Due to the 3 different calendars, I suggest not focusing on duration - but rather work and task start and finish dates.  If you are using auto scheduled tasks - you should also not be entering the Start or Finish dates.  Regarding the Gantt chart - particularly when working with 24 hour schedules, the bars do not appear correctly.  See if turning off "Round bars to whole days" in the Layout command helps this issue.

    Question 2. Duration/Work relationship. This flows on from my last point. I have used the "Type" field to set tasks to Fixed Duration and Fixed Work (I haven't been using Fixed Units). If I'm performing a task I like to use the amount of work required to determine the duration of the job,

    [Julie] Fine - do not use Fixed Duration for this.  Create the auto scheduled task, assign the resource and specify the work.  Project should calculate the duration based upon the Work and the assignment units.

    however for other resources I like to allocate both a duration and amount of work, as the resource is not 100% at my disposal. An example of this would be a document review. Although it might be two hours work and I have assigned the task on the Site calendar (10 hrs/day @ 100% utilised), this will often tend to take longer than a week to get back to me and so I need to allocate a duration for scheduling purposes and a work for costing purposes.

    [Julie] In this scenario, you would like Project to calculate assignments units to spread the two hours of work out over the week.  Set the task as Fixed Duration.  Enter the 1 week duration.  Then assign the resources and specify two hours of work.  If you view the Task Usage view, you should see the 2 hours of work spread evenly over the 1 week duration.

    If I play around with the Resource effort (by changing the [x%] after the resources name in the Resource field) I can some times get this to work, but the reality is it would be a two hour block of time spent at some stage during a weeks period (as an example) rather than 24 minutes per day for five days (what I am actually factoring in). How do I go about approaching this? Should I be setting predecessor/successor relationships rather than a duration?

    [Julie]  If you are content spreading the two hours over the week - I think that is okay.  If you would rather say it's a shorter duration with two hours of work, then a review by another party, then back to the resource for formalizing - that does argue for separate tasks with predecessor/successor relationships.


    Question 3. Start/Stop/Start tasks. To try and utilise my resources better Project often splits a single task up to Start, Stop, Start, Stop, Start etc. etc. Is there an option to force a task to be done completely with no interruption? Some of my tasks might only be a days work and it would make sense to allocate a full day for this task rather than an hour here, an hour there, etc. etc. Furthermore if the schedule shows the task starting and stopping multiple times it might actually increase the amount of work (in reality, if I worked to the schedule) due to the time it takes starting up a task again. Any advice here? Side note - I would rather leave time un-utilised than this Start/Stop/Start business as I have other work I could be doing in this time.

    [Julie] I'm guessing you are using Resource leveling and allowing tasks to be split?  Turn off the option "Leveling can create splits" when you level. 

    Question 4. Task hierarchy. I've ended up giving up on the Auto scheduler a lot here because I can't seem to set up a top - down hierachy in my schedule without forcing constraints that aren't actually constraints. For example I have a work scope, a budget and a schedule (yes I'm scheduling doing the schedule) in my schedule which all have to go through a draft, review, revise, approve, issue sequence. Due to right clicking on conflicts and rescheduling (auto schedule) the tasks are now shown in an illogical order, e.g. complete the document drafts in one order but then revise them in a different order, to the extent where its actually creating a bottleneck on subsequent tasks. The only way I have been able to work around this is by then forcing the tasks to a Manual Schedule, as the moment I try playing around with Start/Finish constraints on Auto Schedule it starts pushing out the schedule and then when I delete the constraints the schedule doesn't "refresh" back to reduce the critical path. Is there some kind of flush function that will delete all Start and Finish dates that haven't been manually scheduled or constrained, and then re-populate all of the dates? That would be really handy.

    [Julie] Not sure I follow 100% here.  Usually when seeing "task hierarchy" I think summary tasks and detail tasks.  Are you using summary tasks to summarize the 'draft', 'review' phases?  If you have typed in dates on Auto scheduled tasks, you have created Start No Earlier Than constraints (if you have typed the start date) or Finish no earlier than constraints (if you have typed the finish date).  To remove all those constraints, select all tasks, click the Information icon on the Task tab, and on the Advanced tab in Task Information, set the constraints to ASAP.

    I hope this helps.

    Julie


    Wednesday, March 6, 2013 1:48 PM