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Network Diagram / Logic Diagram Cluttered and Unreadable

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liversounds
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There is a Primavera schedule report that shows predecessor and successor relationships, including type of relationship and lag. I would like to have something visual that would complement this.

None of the serious schedules I have built or seen are simple enough to be readable in either a network diagram or logic diagram. Instead, they look like a huge spider-web of cluttered complexity with the relationship lines all bleeding together. Granted, if I filter to a small set of activities then I can follow the relationship lines, but then I am only seeing a small section of the schedule and won't necessarily be showing all of the relationships.

Any success stories out there in creating a visual "flowchart" that shows the inner workings of a complicated schedule? Any software making this more simple?

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Seve Ponce
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Liversounds, have you seen NetPoint by PMA Technologies? It best handles up to 300 activities, so really more for level 1 or 2 or for importing a subset from P6. What you can show is still limited by page size, but if you use a larger page size you can show more, especially since you can have multiple activities per row...

Rafael Davila
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Time scaled logic diagrams are essentially Gantt Diagrams without the table. A similar graphical representation of the same thing is so redundant I wonder why they still exist as separate functionality.  The difference, that tandem activities might be aligned on the same line on the network diagram is more of a drawback than an advantage as it prevents the alignment of the table with the lines and makes difficult the sorting and grouping as defined by the user. Gantt Diagrams can display more, not just the table but also late bars and baselines. On complex jobs they can become quite big therefore some tweaking is in order as you already figured out, but tweaking the Gantt is what we do every day, is easier.

The problem with areas is that it is usual for some activities to have links on other far away areas you might be missing. As the project is being created or updated these links might change. It is safer to filter for all linked activities to the selected group and either display the Gantt or the Time Scaled Network.

The following is a Gantt Diagram without the table, filtered for all activities linked to activities within an area(selected). The filter will display not only the activities within the area but also their predecessors and successors belonging to other areas as well  in a concise way that will not miss any single link to other areas. Is easy, fast and do not require creating filters or special codes to include all links, some of which might be missed if using activity codes alone. Keep it simple, especially if you are on the process of schedule development.

 photo scaleddiagram_zps5bd70397.jpg

If you want to see two levels of predecessors and successors for the whole selection, instead of for a single activity, just select all filtered activities and apply once again the filter for selected activities, very easy.

Ronald Winter
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The Timescaled Logic Diagram (found under the Tools menu in P6v7SP5 and P6v8) can be tweaked to show a reasonable network (although the P3 one is still better.) 

You need to set-up activity codes that group related activities (such as by Area) and Group on this.   This causes the relationship lines to shorten and not go vertical across the page. Then there is the sort option which fine-tunes the activity placement. 

Sorting on Total Float will place the critical and near-critical activity bands near the top of a Group.  Sometimes sorting on Responsibility or work type helps. 

Lastly, you really need to plot/print to a large size sheet (Arch D is preferred) in order to reduce connectors.

It can take a while and a lot of trial and error but a very clear and impressive Timescaled Network Diagram can be produced.  It is still the absolute best way to brief upper management on the flow and problems of the project.  Good luck!

Stephen Devaux
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"I am trying to engage project leads and department heads in the "guts" of the schedule, and so I do not want to only show driving relationships."

I completely agree with this -- it is not enough to just show driving relationships, as the float of the non-driving relationships and non relationships (i.e., parallel paths) are key to computing the drag of the critical path activities. And it is bad enough to have "a huge spider-web of cluttered complexity" -- but when despite all its complexity, it nevertheless fails to show the most important info (i.e., critical path drag and drag cost), that really is unfortunate. I have found that it is showing those two metrics to the project team and subcontractors that has the most impact:

("You mean that our activity taking 20D is making the project 9 days longer and potentially costing $900,000? Wow! Y'know, I think we could reduce the duration to 10 days by doubling the resources. It would cost you an extra $200,000; but if we reduce the drag to zero and save $900,000 in drag cost, from this chart it looks like the project would be 9 days shorter and we'd be $700,000 better off.")

Unfortunately, Primavera is significantly lacking in that it does not compute critical path drag. One can of course compute critical path drag "manually" -- but with large and complex networks, it's very complex and time-consuming. Plus which, once you make one cahnge, you often have to recalculate everything! At the moment, only Spider and the Sumatra.com add-on to MS Project do the calculation. I am told there may be other products that do drag coming along fairly soon, but Primavera is not one of them, as far as I know.

Fraternally in project management,

Steve the Bajan

Mina Soi
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Hi everyone,

I am a HND Buiilding Studies student.  I will be grateful if anyone could share with me a copy of WBS and fractional network for a retail unit or office building.

Much appreciated.

Mina

 

 

In Spider Project there is a useful feature that enables group work. If you will create Responsibility WBS grouping activities by persons responsible for their planning and execution the software will replicate project database and each responsible manager will get his part of the project schedule (function is called Distribute subprojects). They can work with their subprojects, create new links, add and edit activities, enter actual data. All changes will appear in the initial schedule when Consolidate subprojects function is selected. All external dependencies will be restored automatically.

Rafael Davila
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Although I prefer a 1000x the links table to disclose all logic in the absence of such table I recall using Trace Logic in SureTrak showing 2 levels of successors and predecessors. Yes it is kind of a filter, cumbersome and time consuming, impractical for reporting all activities but better than using the PERT Diagram alone. For isolated sections can do the trick of bringing into the display far away activity boxes. Definitively a links table I can filter and sort is my first choice.

My next choice to the links table is usually a GANTT Chart filtered for selected activities at a click of the mouse as well as links filtered for selected activities at another click. It will display all predecessors and successors linked by logic as well as linked by resource dependencies on a graphical time scaled view with a table. Will be missing data such as the calendar for the links and therefore it is why this would be my second choice.

 photo tracelogic_zps34067f99.jpg

BTW the following figure displays resource dependencies in dotted lines, these are created automatically and changed automatically, preventing errors and the extra work if creating them manually and deleting them to unstatus before resource leveling.

 photo resourcedependencies03_zpsdd35824e.jpg

Good Luck.

liversounds
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I did not think my words so important to deserve being posted 5 times... The website kept timing out and I thought I was only saving the post one time. I would delte if possible.

liversounds
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Schedules are often complex regardless of the planner and their needs for existence.

I am trying to engage project leads and department heads in the "guts" of the schedule, and so I do not want to only show driving relationships. What I need are tools that help me share ownership of the entire schedule with the folks responsible for executing the work. Currently I do this by sitting down with them--with Primavera open--manually going through all relationships... this is problematic because of time and attention considerations.

Rafael Davila
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Mike,

Your procedure will not be valid if you do not identify resource dependencies that are driving a resource leveled job. Lack of resources will be delaying some activities, you must identify the resource delayed activities as well as the resource availability that is causing such delay. Then by filtering the resource dependencies as well as the driving links you will be able to follow most of the drivers.

Still other constraints such as financial constraints or date constraints can be driving your schedule and you cannot overlook near critical paths.

If your software is capable of displaying resource dependencies as a special link type then you shall be able to display them on your Network Diagram. This will display some of the otherwise missing information, it is not going to make it any simpler but better as an analysis tool.

It is naive to believe on complex jobs the network diagram will tell it all, but when looking at it at least use it to its fullest, display the active resource dependencies.

Best Regards,
Rafael

Mike Testro
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Hi Liversounds

This a common problem with most planners who justify their existance by making things unnecessarily complex.

My way round is to convert a P6 file to Asta PowerProject then isolate the driving links and give them a seperate category and then group all the non driving links and delete them.

Reschedule before saving to see if any key milestones change and then reconvert to P6.

Best regards

Mike Testro

Rafael Davila
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Logic alone is the easy part, on resource leveled jobs it is just the tip of the iceberg. Here you shall look at driving links as well as at driving resources. Delay reason in combination to a links table that displays "resource dependencies" is key to understanding what is driving your schedule.

I find network diagrams useless unless filtered, this is the view I almost never use.

 photo delayreason_zps5467b092.jpg

 

 photo delayreason02_zpsd0db0b25.jpg