MS Project Fixed Duration vs Working Times

[datadrvn]

I've read several posts and still cannot address my problem.

I have a fixed duration task, not effort-driven. The standard calendar and default working times are 8h/d and no holidays.

I then create a task, ex: Start = 1/3/11 ; Dur = 21 days and no resources assigned yet. MSP derives a Finish date of 1/31/11, which is appropriate. However, if I then change the default work week to 7.5h/d (37.5h/w), MSP recalculates the Finish to be 1/28/11.

I don't understand why. I expected the duration to remain as 21 days; Finish to remain at 1/31, which is 21 work days, but the work would have calculated out to 157.5h. Help? Or point me to where I need a working time 101?

[SUpER CoP]

I think that you have to set each task up as fixed duration. Select the tasks, then go to Project/Task Information/Advanced tab. Set the task type to fixed duration and clear the effort driven option. Set the Duration field to be the length of time in working days (e.g. 10 days) or calendar days (e.g. 12ed) during which the tasks must be performed. Enter the effort in the Work field and assign resources. Project will automatically spread the work linearly over the duration span. Use the Resource Usage view to enter Actual Work on a daily basis.

[JulieS]

I've read several posts and still cannot address my problem.

I have a fixed duration task, not effort-driven. The standard calendar and default working times are 8h/d and no holidays.

I then create a task, ex: Start = 1/3/11 ; Dur = 21 days and no resources assigned yet. MSP derives a Finish date of 1/31/11, which is appropriate. However, if I then change the default work week to 7.5h/d (37.5h/w), MSP recalculates the Finish to be 1/28/11.

I don't understand why. I expected the duration to remain as 21 days; Finish to remain at 1/31, which is 21 work days, but the work would have calculated out to 157.5h. Help? Or point me to where I need a working time 101?

Hello,

I am not seeing the same answers as you are, but that may have to do with the order in which I did things. When I create the 21 day task starting on Jan 3, 2011 I too get a calculated end date of January 31. I assign one resource and see 168 hours of work calculated (21*8).

If I then go to Tools > Options, Calendar and change the hours per day to 7.5 and hours per week to 37.5, the duration value is set to 22.4 days but the finish date is still Jan 31 and the work is still 168 hours. The duration value increases because you've now said there are only 7.5 hours in the day and 168 hours of work divided by 7.5 is not 21 -- it is 22.4.

So, to clarify -- did you change the Standard calendar through Tools > Change working time? If I change the resource's calendar to 7.5 hours per day I get a message saying the resource is assigned outside of the original dates and it will change the duration of the task. Did you see the message as well?

You note that you have not assigned resources -- until you assign resources Work is meaningless to Project.

Also, to help track this down -- what version (2003, 2007, 2010) of Project are you using?

If you can explain a bit more about what you want to see, perhaps we can be of more assistance.

Julie