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Calendar for scheduling Relationships Lag

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Luis Garrido
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Hi,

I have the following issue regarding how Primavera calculates lag between activities depending on the "Calendar for scheduling Relationships Lag":

 

I have inherited a programme that has been set to calculate lag with the 24 Hours Calendar. That programme uses 3 kinds of calendars for different activities:

  • 5 days/week 8h/day calendar
  • 6 days/week 8h/day calendar
  • 7 days/week 8h/day calendar

This programme is 3 years long programme with around 4000 activities, therefore we only want to meassure durations in days.

Knowing the above I have an issue with the lag between activities, since that lag has to be multiplied most of the times by 3 and add weekends, etc, due to the problem of having different calendars for Scheduling relationships Lag (24 Hours calendar) and Activities Calendars (5,6,7 days/week and 8h calendars). As you can see that is a bit of a mess, so what I want to change the Calendar for scheduling Relationships Lag to Predecessor Activity Calendar, but when doing so, it moves most of the programme activities from where they are.

The final question is: Does anyone know any way of solving this issue? Not changing the lag one by one by hand, and also keeping the activities calendars as they are.

 

Thanks a lot in advance,

Luis

Replies

Kannan CP
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Luis,

As you are using days to measure the duration, provide the lag as 1 day instead of 24 hrs. This may solve the problem.

 

Best Regards

Kannan

Zoltan Palffy
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glad I could help 

Luis Garrido
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Thanks Zoltan.

Zoltan Palffy
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Joined: 13 Jul 2009
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of course it will move your activities thats the whole point. Your only option then is to adjust each activity duration and lag if any. Good luck 

Luis Garrido
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Joined: 3 Jan 2017
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Hi Zoltan,

Many thanks for your answer, but that does not solve the problem, because once I change the calendar for Scheduling Relationships Lag, and reschedule the programme, it will move all my activities. For example, if Activity 1 is linked FS to Activity 2 with 24h lag (1 day with the 24 Hours Calendar), so that activity 2 starts 1 day after activity one finishes, if I change the Calendar for Scheduling Relationships Lag to "predecessor calendar", assuming that Activity one has a 5 days 8h calendar, then, when rescheduling, activity 2 will start 3 days after activity one, or 5 days if there is a weekend in the middle.

 

Any other solution?

BR

Luis

Zoltan Palffy
User offline. Last seen 9 hours 43 sec ago. Offline
Joined: 13 Jul 2009
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under scheduel thne options you have the choice a sto which calendar that you want to use for scheduelig relationships.

you can choose the successors calendar, the predecessors calendar, 24 hour calendar, or the Project Default Calendar. 

So go to schedule then options then at the bottom choose predecesor calendar