Scheduling Dates in SAP-PS

[gocho14]

Hi fellows,

At present I have the following Work Plan, I don´t have any constraints in dates

Now, I need rescheduling the activity "Drawings", before this activity had a duration of 9 days, now the new duration is 4 days, after that I programmed and I got this Work Plan,

Now with that programing, I have the followings problems:

- The critical path is not correct

- The calculation is bad, because the activity "Civil Activities" must start in 27/01 and not 30/01

Thanks in advance

[former_member201206 · Accepted solution]

Hi Cesar,

I think, it is the typical 'enlarge the duration works, but the shorten the duration does NOT work as expected'.

The reason is as the consulting note 683940 described about the initial dates determination for the scheduling:

How are initial dates determined for activities?

If you selected scheduling type 'WBS determines dates', the earliest start
date of the activities is defaulted from the respective WBS elements in case of
forward scheduling (or the latest finish date of the activities in case of
backward scheduling).

Example:

Activity V_1 is assigned to WBS
element P_1,
Activity V_2 is assigned to WBS element P_2.

In case of
forward scheduling, activity V_1 gets an initial start at the same time as WBS
element P_1 is started, activity V_2 gets an initial start at the same time as
WBS element P_2 is started.

Back to your example, the activity 'Civil activity' has the initial date from WBS 'Constructor' or the network header. I suppose, it is the 30.01.2015. The forward scheduling can only move it in the future, but not in the past.

If other logic is really needed and you have network determined date is set, you can use the modification note 644178. Other alternative is to change the network header or the WBS  of the activity 'Civil activity' ) basic start- dates before you start the scheduling.

Kind regards,

Zhenbo

[gocho14 · Accepted solution]

Hi Zhenbo Wang, Thanks for your help, I'm so thankful for your support

[kenmelching]

What are your scheduling parameter configuration settings?

The activity duration should be an input and not a result of scheduling.  Let the system calculate the dates.

If you have hard dates than use constraints.

Also run overall network scheduling rather than rescheduling a single activity.

[gocho14]

Hi Ken,

that´s my scheduling parameters configuration settings...

In fact I ran overall network scheduling and got that result

[MTerence]

Hi Cesar,

You need to have relationship in place, then only system can change the date as per the previous activity.

Else, you can re-schedule the Civil Activities by changing the start date.

Regards

Terence

[gocho14]

Hi Maria, thanks for your comments, but it´s mandatory change the start date in Civil Activities?

I think to SAP should updating this dates automatically

[sanjeevc]

Hi,

Change the dates accordingly then try to reschedule the project.

if still error is coming let me know what is that and do RnD test on it based on scheduling parameter.

Regards,
Sanjeev

[gocho14]

Hi Sanjeev, I changed the dates and reschedule but the error still persists

I appreciate your help with this, thanks in advance