Relationship Links

Everything you need to know about links

Relationship Links are the relationships between tasks. Links can only occur between tasks, and not between anything else.

Links (and durations) are the drivers that dictate when tasks start (and finish). This is calculated in CPM software (Oracle P6, Microsoft Project, etc.). That data is exported from the CPM software.

FS Relationship Link in blue

Imported vs Manual

By default, all relationships are imported, placed, and hidden in TimeTable. You can reveal these relationships by using the Show Links command in the Ribbon

Imported Relationship Links cannot be modified or deleted. Their shape can be moved, however. Links that are placed manually can be modified and deleted. There is no visual distinction between imported and manually placed relationship links.

Getting more info

Double clicking on a link shape will present the shape data window

Definitions

Data

Definition

Link

The name of the shape

Predecessor

The task id of the predecessor

Successor

The task id of the successor

Type

The relationship type: FS, FF, SS, SF are possible

Lag

The minimum length of the relationship in work days

Duration

The actual length of the relationship in work days

Duration (elapsed)

The actual length of the relationship in calendar days

Slack

= Duration – Lag. The amount of extra time the relationship has.

Lag Format

Hidden

Begin

The predecessor's start or finish

End

The successor's start or finish

Replacing the text

By default, no text is displayed on any links. Right-clicking on a link gives you the option to Edit Text and write anything you want. It is possible to change the text at anytime.

Driving link vs non-driving link

Driving links are links where the Duration is the same as the lag. If the duration is longer than the lag, then it is a non-driving link.

Relationships and durations drive the start and finish dates for tasks. Sometimes redundant links exist for any number of reasons. The ones that can be removed without affecting the schedule at that moment in time are considered non-driving links.

Critical vs Driving links

Critical links are Driving links where the predecessor and the successor are both marked as critical.

Intra-WBS links

Intra-WBS links are relationships that occur between tasks that are in the same Work Breakdown Structure. These links can be hidden, regardless if they are driving or not.

Manual placing and Reversing Links

To create a relationship between two tasks, click on the New Link command in the TimeTable ribbon. Drag the ends of the link to its corresponding tasks.