I would check for outside links to other projects. I had an issue before where I had an outside link that was causing the negative float. The project was actually deleted and still showed a link somehow, but after I found it and removed it the float corrected itself. If this is not the case, then from my experiences, it is most likely a constraint that is causing the problem.
Member for
21 years 8 months
Member for21 years8 months
Submitted by Rafael Davila on Sun, 2011-11-06 11:29
Definitively Negative float is always caused by a constraint – you just have to find it…...
The real challenge is when it is a constraint on the computations placed not by you but by the software like when solving out-of-sequence events. This can be further complicated if your project have outside links to jobs with out-of-sequence events that are driving nuts your schedule late dates computations and therefore your float values.
Member for
24 years 9 months
Member for24 years10 months
Submitted by Patrick Weaver on Sat, 2011-11-05 10:56
Calendar 1 is for a 5 days work week and Calendar 2 is for a 7 days work week. It is the available work days before it becomes critical that matter. What if for Activity 2 the following week have exceptions for all days?
Member for
16 years 7 months
Member for16 years7 months
Submitted by Gary Whitehead on Wed, 2011-11-02 08:51
One final point is that Float is measured in working days not calendar days, so a negative float of -200 days using one activity calendar, could equate to a negartive float of -40 days on another calendar.
Check the activity which has the latest date and keep following the predecessor link,you can get info about the relationships and lag used which might be illogical
Cheer's
Shahul
Member for
21 years 8 months
Member for21 years8 months
Submitted by Rafael Davila on Tue, 2011-11-01 14:08
There are two primary causes of negative float on activities.
1. If a Must Finish By constraint is assigned at the project level, this could cause negative float if the project cannot be completed by the constraint date. Check the Must Finish By date in Projects View, Dates tab.
2. If a mandatory constraint is assigned to an activity, this could cause negative float if the predecessor activities do not have enough time to finish. Run a schedule report to check for constraints.
Other possible sources of negative float:
Out of sequence progress. Correct the logic in the schedule or schedule using Progress Override or Actual Dates.
Different Calendars on activities.
External project(s) with constraints that have relationship ties to the schedule. Check the Advanced
Scheduling option "Ignore Relationships to and from other projects"
Backward leveling. Reschedule to remove the leveling
My observation is that people tend to overlook the out-of-sequence and leveling reasons as well as outside links.
After resource leveling negative float makes no sense, it becomes meaningless.
How the out-of-sequence impacts schedule calculations is one of the reasons I believe all out-of-sequence events shall be fixed, even in the absence of resource leveling. You never know and might not notice if the impact is not obvious.
Regards,
Rafael
Member for
17 years 9 months
Member for17 years10 months
Submitted by Mohammad Mojah… on Tue, 2011-11-01 13:50
Member for
13 years 11 monthsI would check for outside
I would check for outside links to other projects. I had an issue before where I had an outside link that was causing the negative float. The project was actually deleted and still showed a link somehow, but after I found it and removed it the float corrected itself. If this is not the case, then from my experiences, it is most likely a constraint that is causing the problem.
Member for
21 years 8 monthsDefinitively Negative float
Definitively Negative float is always caused by a constraint – you just have to find it…...
The real challenge is when it is a constraint on the computations placed not by you but by the software like when solving out-of-sequence events. This can be further complicated if your project have outside links to jobs with out-of-sequence events that are driving nuts your schedule late dates computations and therefore your float values.
Member for
24 years 9 monthsNegative float is always
Negative float is always caused by a constraint – you just have to find it…... To understand how the calculations work in most scheduling tools see: http://www.mosaicprojects.com.au/PDF/Schedule_Float.pdf
Member for
21 years 8 monthsFloat is based on activity
Float is based on activity calendar.
Calendar 1 is for a 5 days work week and Calendar 2 is for a 7 days work week. It is the available work days before it becomes critical that matter. What if for Activity 2 the following week have exceptions for all days?
Member for
16 years 7 monthsOne final point is that Float
One final point is that Float is measured in working days not calendar days, so a negative float of -200 days using one activity calendar, could equate to a negartive float of -40 days on another calendar.
Member for
16 years 11 monthsHi Glecy Maranan In Addition
Hi Glecy Maranan
In Addition to Mr.Rafael's Information
Check the activity which has the latest date and keep following the predecessor link,you can get info about the relationships and lag used which might be illogical
Cheer's
Shahul
Member for
21 years 8 monthsFrom:
From: https://forums.oracle.com/forums/thread.jspa?threadID=881584
There are two primary causes of negative float on activities.
1. If a Must Finish By constraint is assigned at the project level, this could cause negative float if the project cannot be completed by the constraint date. Check the Must Finish By date in Projects View, Dates tab.
2. If a mandatory constraint is assigned to an activity, this could cause negative float if the predecessor activities do not have enough time to finish. Run a schedule report to check for constraints.
Other possible sources of negative float:
My observation is that people tend to overlook the out-of-sequence and leveling reasons as well as outside links.
Regards,
Rafael
Member for
17 years 9 monthsDear Please check in
Dear
Please check in setting
Total float is less than or equal to ( 0 )