Class Relations

Class relations determine which classes can be related to each other, which in turn determines the objects and design parts that another object can be connected to. Class relations, in a large part, determine the from/to navigational structure of a design object and can be configured to display the countless variations that may exist within a plant. For example, relations for the MOTOR class can be set up to show each motor's attached cables (Leaving and Arriving), the room the motor is located in (e.g., Location: 10), and its junction box connection (e.g., 10-JB-001).

Class relations simplify the registration process by limiting the number of relations that appear in the List of Values, which ensures that only appropriate relations can be made. For example, when registering a transmitter, the only possible functional parent relation to select from would be an instrument loop. Class relations are defined for both design parts and object classes.

The Class Relations window is used to configure relations. All relations are configured on a per-class basis; that is, all pumps in the PUMP Class share the same relations. Customized relations can be created using the default relations as templates. Ordinarily, classes are created and their relations are configured afterwards. However, the required class relations may influence a class more than the class's technical data or ID designation.

Object Connection Types

Objects are the focal point for the main relations to other objects, design parts and documents, among others. Each of the relations below can be applied bi-directionally. The object classes listed in the table below are examples; they illustrate how an actual relation might read.

N	An Object of Class	Class Relation Description	Object(s) of Class	N
1	CIRCUIT	can have free functional children	TRANSMITTER	n
n	TRANSMITTER	can have a free functional parent	CIRCUIT	1

1	BUILDING	can have free locational children	ROOM	n
n	ROOM	can have a free locational parent	BUILDING	1

1	PS_DATA	can be process data for	VALVE	n
n	VALVE	can have process data	PS_DATA	1

1	CIRCUIT	can use signals from	SIGNAL	n
n	SIGNAL	can be a signal for	CIRCUITS	1

1	MCC (Motor Control Central)	can have leaving	CABLE	n
n	CABLE	can leave from	MCC	1

1	MOTOR	can have arriving	CABLE	n
n	CABLE	can arrive at	MOTOR	1

Dynamic Object Relations

Relations are bi-directional - defining the relation in one direction also defines it in the other direction. The following object relations can be modified as necessary. The object classes are examples used to illustrate the connection types.

N	An Object of Class	Class Relation Description	Object(s) of Class	N
1	MCC_COMPARTMENT	can supply	MOTOR	1
1	MOTOR	can be supplied by	MCC_COMPARTMENT	1

n	RELIEF_VALVE	can affect	PRESSURE_VESSEL	1
1	PRESSURE_VESSEL	can be affected by	RELIEF_VALVE	n

n	SIGNAL	can assign	CHANNEL	1
1	CHANNEL	can be assigned to	SIGNAL	n

1	MCC	can preliminarily supply	MOTOR	n
n	MOTOR	can preliminarily be supplied by	MCC	1

1	MOTOR	can drive	PUMP	1
1	PUMP	can be driven by	MOTOR	1

n	CIRCUIT	can preliminarily assign	DCS	1
1	DCS	can preliminarily be assigned by	CIRCUIT	n

n	TRANSMITTER	can be located next to	PIPE	1
1	PIPE	can have closely located	TRANSMITTER	n

1	MCC_COMPARTMENT	can supply as spare	MOTOR	1
1	MOTOR	can be supplied by spare	MCC_COMPARTMENT	1

1	MCC	can supply as spare	MOTOR	n
n	MOTOR	can be supplied by spare	MCC	1

1	PIPE SYSTEM	can have pipe parts	VALVE BALL	n
n	VALVE BALL	can have a pipe parent	PIPE SYSTEM	1

n	PUMP	can have an additional part	IMPELLER	n

Design Parts Connection Types

There are three, bi-directional default design part connection types that can be applied. Each design parts class listed below is an example: they exist only to illustrate the connection type.

N	A Design Part of Class	Class Relation Description	Object(s) of Class	N
1	MOTOR	can be a design part for	MOTOR	n

n	IMPELLER	can be an additional part for	PUMP	n

	A Design Part of Class		Design Parts of Class
n	PUMP	can consist of	IMPELLER	n
n	IMPELLER	can belong to	PUMP	n

Design Objects and Parts Related to Objects

The definition of design objects and parts related to an object on Design Object windows is governed by the object relations defined for a particular class. When connecting the relation to the object, each relation may receive just one value. One or more of the following relations may be added:

Locational Parent - a free locational (physical) parent object relation.
Functional Parent - a free functional (logical) parent object relation.
Process Object - a flow or stream data object assigned in a 1:1 relation to a Piping, Instrument, or Process & Mechanical object.
Circuit - this n:1 relation is for Signals and is used for a Circuit Loop (functional parent).
Pipe System - this 1:1 relation describes a pipe line's parent pipe system object.
From Object - a 1:1 relation that gives an overview of a mini-system and can simplify searching for connected objects. For example, searching for a main pipe object lets you also look at the two objects that appear on either side: e.g., a pump (From Object) and a tank (To Object). This relation is used in conjunction with To Object.
To Object - Used in conjunction with From Object.
Design Parts - A piece of equipment that technically fulfills the object's functional requirements. Most objects will have a related design part.

Adding Relations to Objects

New relations can be created in several different ways. Always make sure the relation is permissible (as set under Class Relations) before trying to define a value for it.

Add a main object relation on the Design Object window.
Within the Business Object Explorer for design objects, drag Functional and Locational children from a tree view to another Object. This is a quick and easy way to create relations, especially since only valid relations are permitted.