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Primavera Can’t do this. Getting desparate

5 replies [Last post]
Tue, 2009-03-31 13:08
David Kelly
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Can Open Plan do this?

Resource levelling and mandatory lag

Example.

A work instruction becomes an activity in P6.

Work instruction “a” is an isolation of a piece of equipment.

Work instruction “b” is the work to be performed when the isolation has been performed.

It is essential that the work is performed immediately after the isolation is performed.



A finish-to-start relationship does this very well when scheduling. Unfortunately since there is no “mandatory lag” capability in P6, when the project is levelled, there is no way to ensure that activity “b” follows immediately after activity “a”.

Any Ideas team?
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Replies

Wed, 2012-04-04 16:52
#1
Jorge Payne
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Have activity 'B' be the FS predecessor to activity 'A'.  Then apply a lead equal to the duration of B + 1.  Now if activity B gets postponed by other predecessors, A gets pulled along also "just in time".  Notice that A will never drive B since its not a predecessor, but its early dates will always immediately preceed B.  This works whenever you have an activity with shelflife.

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Wed, 2009-04-01 20:20
#2
Vladimir Liberzon
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In Spider Project it is called strong link.
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Wed, 2009-04-01 06:53
#3
Gary Whitehead
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I’ve never levelled in Open Plan and now I don’t have the software to try it out, so can’t help you there.

Would a work-around be to combine instructions a and b into one? Maybe with a zero-resource activity acompanying if you need to show the specific isolation date?
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Mon, 2009-04-27 13:36
#4
Keith Courneyea
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In Open Plan set Resource Scheduling ’Type’ on the Advanced tab of the Activities dialog box to the value of ’Immediate’. This will cause the activity to be scheduled immediately after it’s logical predecessor. Use this sparingly.

Keith
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Mon, 2009-04-27 19:26
#5
Rafael Davila
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If your software, Open Plan or P6 have zero float constraints as Suretrak does then you can schedule the successor activity with a f-s link from the predecessor along with a zero float constraint then with a lag on this link you probably will get a mandatory lag.
To see if this holds true after resource leveling try it in your software, then run the resource leveling and let us know.
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