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How do you avoid having negative float?

10 replies [Last post]
ladi sodipo
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When i load my project into P5 from MSP and start putting in actuals, some tasks start having negative float, this is not the case when i build out my plan, but once i start putting actuals, i start getting negative float, Is there a way i can stop this from happening or better still correct the negative float.

Thanks.

Replies

Stephen Devaux
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Anning Sofi wrote:

"This is not a simple computer exercise to tweak the programme so there will be no delay. You have to identify the cause of the delay, and have your organization work out ways to recover from slippage"

Right on, Anning.  Negative float is how the software tells the user that something is projected to delay your project. Any time you have negative float, you have to identify what's causing it (work slippage, NET constraints, resource insufficiencies...) and what you're going to do about it (extend the project duration or recover the schedule and change the work plan).

If you had Spider Project or MS Project instead of Primavera, the way to go about recovering the schedule would be quite starightforward: determine which activities (or constraints) have how much Critical Path Drag, reduce the amount of their Drag and thus the length of their path, see if the CP goes elsewhere and where the Drag is on the new CP, reduce those Drags, etc.  It's not always the easiest thing to DO, but the data regarding the possible options is very straightforward to generate.

The failure of Primavera to compute Critical Path Drag is a huge shortcoming.  With projects of fewer than 200 activities, it is simple enough to compute Drag "manually" -- but on larger projects, it can be extremely time consuming, requiring a lot of work for each iteration.

Fraternally in project management,

Steve the Bajan

Anning Sofi
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When you say you are putting actuals, and the programme starts gving you negative float, what that means is that there is delay? Why would you remove them? This is not a simple computer exercise to tweak the programme so there will be no delay. You have to identify the cause of the delay, and have your organization work out ways to recover from slippage

Raymund de Laza
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Hi Mr. Hilal,

There is (-1349) days Total Float on your reply. Mr. Ladi requres the reply before 1349 days.

 

Cheers....

Hilal Hallani
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Hello Ladi,

If you have any constraints (which I hope you dont) you need to remove them. In project details, your "must finish by" date must match your finish date in your programme. This should work, if it doesnt, then you need to reorganise your logic.

Regards

ladi sodipo
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Interesting, Thanks Ya’ll.
Andrew Dick
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Maybe get a job in the BD department?????

They’re optimistic little buggers, and always say that we have heaps of time to deliver a $1Bn job in 6 weeks with 2 blokes from the corner pub, two shovels and a meat pie...
Stuart Atkinson
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Negative float may be appearing when activities are updated and are starting sooner than the logic tells. That is,
if you update the task woth a start date and the preceding task which it is dependant on has not finished, negative float will be created. They are out of the original sequence. Hope it helps.
Alex Wong
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I call this cosmatic planning - How can you avoid having negative float ... impossible ... unless the project dont have a deadline ....
Satya Narayana
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Negative float is the other way of expressing the delay, if you do not want that remove the constraints and ur updated project goes beyond the planned project completion date.
Zhang Haixiang
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check you schedule and find out the constraints, and remove them.