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 Use of Relationships


Most orders in Plant Maintenance are planned and executed without any particular relationship between the individual operations.

However, you should consider using relationships if:

  • You want to have extensive, detailed shutdown planning

  • Certain operations must be executed in parallel, or in a particular sequence

  • You want to use a different sequence of operations to the normal sequence automatically used in the standard system

You can create relationships manually or generate them automatically.

Caution Caution

Note that you can only network operations together using relationships; you cannot network sub-operations together.

End of the caution.


When you use relationships in the order, you give the order the main properties of a network from the Project System (PS).

For more information about networks, see PS - Project System .


Before you start networking order operations, you should consider whether the finish-start relationship generated automatically, which is valid for an order without explicit networking, is sufficient for your requirements.

You should only create networks between the individual operations if you are sure that you want a different relationship between the individual operations or parallel operations.

The following prerequisites must be met before you can create and maintain relationships:

  • An order must be created.

  • The order must have several operations.

Note Note

If you want to use a profile other than the standard profile for the graphical display, you must define one using the Customizing function and assign it to the required system users.

End of the note.


Creating Relationships Using the List Function

A list is available for entering relationships.

Creating Relationships Using the Graphic Function

In addition to the list, a graphic is also available for entering relationships.

Entering Operations for Relationships Using the Graphics Function

If you are entering or changing relationships in the graphic function, and realize that a certain operation has not yet been entered, you can enter it in the graphic.

Generating Relationships Automatically

If at least one relationship already exists between the operations of two or more orders, you can generate relationships automatically between all the operations not yet linked by relationships. The relationships generated in this way belong to the FS-relationship type.

You can thereby prevent all the operations, between which no relationship has been created, from being scheduled at the same time as the first operation.

This function can only be executed if at least two operations have already been linked together. If this is not the case, the operation number determines the scheduling sequence.

The function can be executed by choosing Start of the navigation path Order Next navigation step Functions Next navigation step Dates Next navigation step Generate relationships End of the navigation path .

Networking Orders Using Relationships

You can link the operations for several orders together using relationships. In this way, you create an operation network that links all the specified orders with one another.

The following options are available for networking several orders to one another using relationships:

  • Enter all the relationships for the required orders in the list.

To do this, proceed as described in Creating Relationships in the List .

  • Use the list only for the first relationships between different orders. Then use the graphics function for all other relationships between the operations for the different orders.

To do this, proceed as described in Creating Relationships in the Graphic .

Displaying, Changing and Deleting Relationships

You can display, change and also delete one-time relationships created between operations.

Performing a Loop Analysis

In Plant Maintenance, the operations linked by relationships are executed in sequence within an operation network. Individual operations cannot be networked again. They must not form a loop, since this results in problems when scheduling the order.

To avoid creating such loops, the PM application component provides a loop analysis function. This is a tool that checks whether an operation network contains a loop. You should always call up the loop analysis if you have created new relationships or changed existing ones.