Weird Problem in P6

10 replies [Last post]
adab azeez
User offline. Last seen 1 week 2 hours ago. Offline
Joined: 19 Jul 2016
Posts: 22
Mr. zoltan, I have prepared a schedule in primavera. That comprises a start mile stone, finish mile stone and in between these two mile stones there are 7 WBS having 4 activities each. Calender is 24X7 hrs. And all relationship type are finish to start. I am wondered that after scheduling all my ghant chart bars are showing Red- red every where, i.e. entire project appears to be in critical path. All activities are in FS relationship. I think its wrong. Can you find the mistake ?

Replies

Zoltan Palffy
User offline. Last seen 1 day 6 hours ago. Offline
Joined: 13 Jul 2009
Posts: 1548

GLAD i COULD HELP

adab azeez
User offline. Last seen 1 week 2 hours ago. Offline
Joined: 19 Jul 2016
Posts: 22
Thanks a lot Mr. Zoltan.
adab azeez
User offline. Last seen 1 week 2 hours ago. Offline
Joined: 19 Jul 2016
Posts: 22
Thank you Mr. Steven. Your reply was very convincing and clear.
Steven Auld
User offline. Last seen 1 hour 52 min ago. Offline
Joined: 13 Sep 2017
Posts: 31

adab,

If ALL activities are linked Finish to Start, then all activities should be on the Critical Path, as there is only 1 path.

The first activity of WBS 1 is linked to the Start Milestone, then all activities linked Finish to Start under this WBS. 

If the Last Activity of WBS 1 is linked to the First Activity of WBS 2 & this sequence is repeated through all the WBS Levels, with the last activity of WBS 7 being linked to the Finish Milestone, then there is 1 path so all activities will be critical.

If the WBS Activities are linked as shown in Jithin's post & the total duration of each path is the same then all will be critical, as you may have 7 different paths from the Start Milestone to the Finish Milestone - The Float for each path would be the same & all activities would be driving the critical path.

If 1 activity took longer during execution, then this path would become the critical path.

If you increase the duration of 1 activity, do all activities remain critical, or is a new critical path identified?

Do you have any constraints applied on your Project?

Steven

adab azeez
User offline. Last seen 1 week 2 hours ago. Offline
Joined: 19 Jul 2016
Posts: 22
Hello Steven. Yes there is relationship between WBS of finish to Start.
Steven Auld
User offline. Last seen 1 hour 52 min ago. Offline
Joined: 13 Sep 2017
Posts: 31

adab,

Am I misreading your last post:

"Is it possible that even in a small project of primavera having 5 or 6 activities all in Finish to Start relationship, All activity will become red in ghant chart?"

If ALL activites are linked Finish to Start in a small project, then ALL would be Critical & Red in the Gantt Chart.

Are there any relationships between the different WBS? 

Steven

Zoltan Palffy
User offline. Last seen 1 day 6 hours ago. Offline
Joined: 13 Jul 2009
Posts: 1548

if you have a constraint date or a project must finish by date that will dtermine the criticaally of it.

if EVERYTHING is FS then depending on the duration it wil dtemeine the critical path 

Jithin Kambhikanam
User offline. Last seen 1 week 2 days ago. Offline

Hi Adab,

May be all the Activity under Different WBS on FS relationship has equal dutation and is pushing the Finish Milestone then all the activity would be Critical. Check that too. 

WBSActivityDurationTotal DurationFloat to Finish Milestone
WBS 1Activity 12  140
WBS 1Activity 2 4 
WBS 1Activity 3  8
WBS 2Activity 15  140
WBS 2Activity 2 6 
WBS 2Activity 3  3

In this all the Acivity would be Critical if under FS relationship.

Regards

Jithin

adab azeez
User offline. Last seen 1 week 2 hours ago. Offline
Joined: 19 Jul 2016
Posts: 22
Thank you Jithin. I have tried all this but sadly its not working. Is it possible that even in a small project of primavera having 5 or 6 activities all in Finish to Start relationship, All activity will become red in ghant chart? Checked bar option too, everything alright there. Schedule option is set to longest path method. Still its happening.
Jithin Kambhikanam
User offline. Last seen 1 week 2 days ago. Offline

Hi Adab,

Look at the Project - Must Finsih Date and then go to Settings of the Project and check what has been selected for "Define Critical Activities.

If you have selected " Longest Path" then the longest path in your schedule would be Critical. 

If you have selected "Total Float less than or equal to" - No days - All the activity which has a total float less or equal to that duration would be critical.

Regards

Jithin