I'd like to ask the experienced guys using constraints in their schedules / programmes as to what is the difference by using the different constraint types.
Start Constraints
- As Late As Possible
- Mandatory Start
- Start On
- Start On or Before
- Start On or After
Finish Constraints
- As Late As Possible
- Mandatory FInish
- Finish On
- Finish On or Before
- Finish On or After
Be aware some software are particularly bad at handling multiple constraints, at times yielding erroneous results.
http://www.planningplanet.com/forums/primavera-version-pm5-pm6/517280/p…
Mike is right, never use them,
And if you have to I would limit it to between 5 - 10% of all activities.
John,
Go to the help menu of primavera and search for "constraints". It will give you a good definition of what the effects of each type are are.
However in summary:
-"Start" types affect start dates, and "finish" types affect finish dates
-"On or before" types affect late dates, and "On or after" types affect early dates
-"On" types affect both early and late dates
-"Mandatory" types will ignore logic to maintain the mandatory date, and calculate total float for preceding activities based on this mandatory date
-"ALAP" pushes an activity out as late as possible without delaying any sucessors (ie zero free float)
Hi John
The correct answer is never use any of them as they distort the logic of the programme.
There is a case to use ALAP on third party milestones such as Power On and delivery of Free Issue Materials.
Also "must start on" for the very first activity milestone otherwise none at all.
Best regards
Mike Testro