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Can MSP calculate Total slack / criticality arising from SS relationships?

5 replies [Last post]
Wed, 2013-01-09 13:14
Gary Whitehead
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I'm reviewing an MSP programme for a colleague. He is concerned that he can't see a critical path running through the project schedule.

The "critical" filter shows the back end of the path, but not any activities upstream of a critical SS + lag relationship

I think this is because MSP is calulcating total slack (aka float) as finish slack, rather than finish or start slack, whichever is lower.

Is there a setting I can change, so that it will take start slack into account for criticality?

 

Obviously, I can suggest that he replaces the Start lag with an activity, and link them with FS to get around the problem, but I also want to give him the option of a settings solution, if one exists.

 

The project was created in MSP 2010, but I am using MSP 2003 to review it.

 

Thanks in advance,

 

G

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Replies

Fri, 2013-01-11 20:44
#1
Rafael Davila
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I believe MSP calculates a Start Slack field, try filtering activities with Start Slack </= 0 and/or Total Slack </= 0.

http://office.microsoft.com/en-001/project-help/start-slack-task-field-HP045335790.aspx

If it works maybe you can edit your bars to show criticality. Try with scarlet bar color to identify critical activities because of start slack while red for finish slack or start&finish criticality.

Keep in mind I do not have MSP so I am not able to try how it works.

Good luck.

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Fri, 2013-01-11 14:39
#2
Gary Whitehead
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Mike / DS Chan: Thanks for the advice. Setting the activity with SS+lag successor to ALAP, or adding an FF+lag relationship to force the criticality does indeed fix the problem (though at the cost of adding a constraint or relationship to the schedule which may or may not be true), but I am looking for a solution that does not involve making any changes to the activities -only to the way MSP calulates the float.

Trevor: Thanks for the offer of help -I've sent you the file

 

Cheers,

 

G

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Fri, 2013-01-11 10:45
#3
DS Chan
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Hi Gary,

''SS + lag relationship'' is not a good pratice for programming, it consists of a open end for the predecessor activity. If use of ''SS + lag relationship'' as logic link, ''FF + lag relationship''  should also be applied for close the path. Please try and see the result.

Best Regards,

DS Chan

 

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    Thu, 2013-01-10 02:37
    #4
    Trevor Rabey
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    Happy to discuss it if I can see it.

    send it to me:

    trevor@perfectproject.com.au

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    Wed, 2013-01-09 16:26
    #5
    Mike Testro
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    Hi Gary

    Try setting all the tasks to ALAP.

    Best regards

    Mike Testro

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