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Free Float and LAG

5 replies [Last post]
Sun, 2011-01-23 12:13
Mohamad Abdelsala
User offline. Last seen 12 years 33 weeks ago. Offline
Joined: 12 Jan 2011
Posts: 18
Groups: Civil Engineering

Hi All,

1st am New hear but i am so happy coz i am a part of this planning planet

2nd What is the Difference between Free Float and Lag?

Regards,

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Replies

Wed, 2011-04-27 14:55
#1
Abhishek Choubey
User offline. Last seen 11 years 50 weeks ago. Offline
Joined: 13 Nov 2010
Posts: 12
Groups: None

Hi..

I think Lag is an offset or delay from an activity to its successor. This could be negative or positive.

 

Regards,

Abhishek

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Sun, 2011-01-23 15:33
#2
Rafael Davila
User offline. Last seen 18 hours 7 min ago. Offline
Joined: 1 Mar 2004
Posts: 5229
Groups: Spider Project Team

1 cyl car

Mike,

Sell your one cylinder car and get something better. Same goes to limited functionality of old CPM, the absence of lag modeling when needed is as bad as its use when not appropiate.

Best regards,

Rafael

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Sun, 2011-01-23 12:47
#3
Mohamad Abdelsala
User offline. Last seen 12 years 33 weeks ago. Offline
Joined: 12 Jan 2011
Posts: 18
Groups: Civil Engineering

thanks mike actually i asked in awrong way , i know the difference but when u gonna to calculate in manually (i am doing this exersice coz i wanna to understand why i need to use zero free float constraint) so while u r calculation it manually in PDM for example its the same formula am i rite?

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Sun, 2011-01-23 12:47
#4
Mohamad Abdelsala
User offline. Last seen 12 years 33 weeks ago. Offline
Joined: 12 Jan 2011
Posts: 18
Groups: Civil Engineering

thanks mike actually i asked in awrong way , i know the difference but when u gonna to calculate in manually (i am doing this exersice coz i wanna to understand why i need to use zero free float constraint) so while u r calculation it manually in PDM for example its the same formula am i rite?

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Sun, 2011-01-23 12:31
#5
Mike Testro
User offline. Last seen 5 weeks 5 days ago. Offline
Joined: 14 Dec 2005
Posts: 4418
Groups: Building Information Modelling, Content Moderators, GPCCAR Editors

Hi Mohamad

Free float is the spare time available between finishing one task and starting another in the same logic sequence.

Lag is an artificial amount of time built into the logic to stop a task from starting or finishing when the natural logic says it should.

Use of Lags is not good planning practice unless it is to set curing period.

Best regards

Mike Testro

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