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Activity Split Relationship

3 replies [Last post]
Nathan Siva
User offline. Last seen 48 weeks 15 hours ago. Offline
Joined: 28 Apr 2014
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Hi Experts,

One of my clients requesting activity split relationship in P6, for example, we have three activities A, B, C. After activity A progressed 20%, activity B has to start and after completion of activity A, C has to start. I recommended my client to Split the activity A into two activities like activity A (Initial) and activity A (Final). After completion of activity A (initial), activity B can start and after completion of activity A(Final), activity C can start. Any other way to show this activity midway relationship in P6?

Replies

Rafael Davila
User offline. Last seen 1 hour 28 min ago. Offline
Joined: 1 Mar 2004
Posts: 5229

P6 does not provide for %volume Lag but only Time Lag.

P6 does not provide for adjusting Time Lag.

https://www.ronwinterconsulting.com/Making_CPM_Transparent.pdf

In-Progress Lag Report and Value: Remaining Lag should be displayed just as remaining duration is shown and editable. The CPM feature of Remaining Duration was added so that Schedulers could monitor and change this calculated duration result. Lags are to relationships what durations are to activities. Why should Remaining Lag calculations be discarded by the software instead of saved and displayed? Why should we be unable to indicate that actual remaining lag is only 2 days instead of the calculated 4 days? Part of the reason CPM Schedules are so hard to understand is that fact that not all of the data used is displayed.

A workaround is to use activities to represent lag.  This will make lag more visible, will allow for lag calendar be independent of successor/predecessor, and will allow adjusting remaining lag.  It will also allow to model lag durations in Monte Carlo simulations when your software does not provide for probabilistic Lag durations. To avoid confusion be consistent, if using activities to represent lag then model all lag as an activity. You can use an activity code to identify lag activities and to filter them.

Activity-as-Lag click image to zoom

Good Luck,

Rafael

Nathan Siva
User offline. Last seen 48 weeks 15 hours ago. Offline
Joined: 28 Apr 2014
Posts: 28
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Thanks for your suggestion Zoltan.

Zoltan Palffy
User offline. Last seen 3 days 10 hours ago. Offline
Joined: 13 Jul 2009
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you can do that or 

have B be a start to start successor to A with a lag equal to 20% of the time this is the same as what you are proposing by splitting the activity. The problem with your method and this method is that 20% of the time may not equal 20% progress.