Website Upgrade Incoming - we're working on a new look (and speed!) standby while we finalise the project

Tips on using this forum..

(1) Explain your problem, don't simply post "This isn't working". What were you doing when you faced the problem? What have you tried to resolve - did you look for a solution using "Search" ? Has it happened just once or several times?

(2) It's also good to get feedback when a solution is found, return to the original post to explain how it was resolved so that more people can also use the results.

Negative Float

5 replies [Last post]
Mon, 2007-01-08 07:08
Alan Muir
User offline. Last seen 17 years 27 weeks ago. Offline
Joined: 8 Jan 2007
Posts: 7
Groups: None
Hello,
I’m a new member and this is my first post, hope it’s successful.

Can anyone list all possible causes of negative float in a P3e plan?
Top

Replies

Thu, 2007-01-11 01:32
#1
Brennan Westworth
User offline. Last seen 7 years 29 weeks ago. Offline
Joined: 23 Feb 2003
Posts: 150
Groups: None
Late start or finish constraints can also cause negative float when the activity logic and durations push past this date.

Negative float = early dates > late dates
Top
Wed, 2007-01-10 09:39
#2
Alan Muir
User offline. Last seen 17 years 27 weeks ago. Offline
Joined: 8 Jan 2007
Posts: 7
Groups: None
Cheers Neil,

You were right on both counts. I appreciate your time & help with this problem.

Thanks,

Alan
Top
Wed, 2007-01-10 05:36
#3
Neil Branigan
User offline. Last seen 8 years 32 weeks ago. Offline
Joined: 19 Dec 2006
Posts: 9
Groups: None
Dear Alan,

You probably have figured this one out already.

Must finish contraints are the root cause of this in my experience. In particular, at a project level in Primavera (P3e) you may place a project ’must finish by’ contraint. This will impact everything as soon as you start progressing your plan.

Another cause of this is when you have "loose logic". Your plan should input/output logic links except for the 1st and last activity! Loose logic causes havoc with your float calculations. However, it mainly gives you huge float values on certain activities as opposed to -ve float.

Cheers
Neil.
Top
Mon, 2007-01-08 11:15
#4
Alan Muir
User offline. Last seen 17 years 27 weeks ago. Offline
Joined: 8 Jan 2007
Posts: 7
Groups: None
Thanks Charlie,

In my research on other sites/forums today I came across a similar sentiment & am now in the process of reviewing all constraints. This seems to be doing the trick. Thank you for confirming that I’m on the right track. Your help & your time are appreciated.

Alan
Top
Mon, 2007-01-08 11:12
#5
Charleston-Joseph...
User offline. Last seen 3 years 17 weeks ago. Offline
Joined: 10 Jul 2005
Posts: 1347
Groups: None
Hi Muir,

There is a big chance the schedule was constraint using "must be finish" dates.

Charlie
Top