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Attributes Attributes in in PDMS PDMS

In document PDMS Basics (Page 43-49)

5.2 Attributes Attributes in in PDMS PDMS

Every element in a PDMS database has a

Every element in a PDMS database has a fixed set of properties known as fixed set of properties known as itsits Some attributes are common throughout the range of elements while

Some attributes are common throughout the range of elements while others differothers differ according to the type of element involved. For example, a cylinder (CYLI) has Height according to the type of element involved. For example, a cylinder (CYLI) has Height and Diameter attributes whilst the size of

and Diameter attributes whilst the size of a box (BOX) is determined by a box (BOX) is determined by Xlength,Xlength,  Ylength and Zlength attributes

 Ylength and Zlength attributes, as illustrated below:, as illustrated below:

Cylinder and Box attributes Cylinder and Box attributes When you create an element, a

When you create an element, a set of appropriate attributes are entered into theset of appropriate attributes are entered into the database. The attributes will vary according to the

database. The attributes will vary according to the type of element but essentially thetype of element but essentially the process is the same. For example, a cylinder has the following attributes:

process is the same. For example, a cylinder has the following attributes:

Attribute

Attribute Default Default ValueValue Name

Name Name Name if if specified specified or or hierarchy hierarchy descriptiondescription Type

Type CYLICYLI

Lock

Lock falsefalse (the element is not locked) (the element is not locked)  Owner

Owner the name of the owning element or its hierarchy descriptionthe name of the owning element or its hierarchy description Positio

Position n N N 0mm 0mm E E 0mm 0mm U U 0mm0mm (relative to its owner) (relative to its owner)  Orientation

Orientation Y Y is is N N and and Z Z is is UU (relative to its owner) (relative to its owner) 

Attribute

Attribute Default Default ValueValue Level

Level 0 0 1010 (this is a representation level (this is a representation level setting) setting)  Obstruction 2

Obstruction 2 (it is a solid hard element for clashing purposes) (it is a solid hard element for clashing purposes)  Diameter

Diameter 0 0 mmmm Height

Height 0 0 mmmm

These are all of the attributes of a cylinder, and all cylinders in

These are all of the attributes of a cylinder, and all cylinders in the database will havethe database will have precisely the same number of attributes.

precisely the same number of attributes.

5.2.1 NAME 5.2.1 NAME

Every element in PDMS can be named. Whether named or not every element will have a Every element in PDMS can be named. Whether named or not every element will have a unique system-generated

unique system-generated . If a name is not specified, then a hierarchy. If a name is not specified, then a hierarchy description will be displayed in the

description will be displayed in the oror (see section(see section 8.3)8.3)..

Internally PDMS uses the reference number since

Internally PDMS uses the reference number since this cannot change. A table of this cannot change. A table of namesnames against reference numbers is maintained for this purpose.

against reference numbers is maintained for this purpose.

 All PDMS names begin with a f

 All PDMS names begin with a forward slash character (orward slash character ( ), which is considered to be part), which is considered to be part of the name. In order to save you the effort of typing this, all

of the name. In order to save you the effort of typing this, all of the forms you encounterof the forms you encounter will add the forward slash for you when you press the

will add the forward slash for you when you press theEnterEnter key after typing a name.key after typing a name.

The forward slash character is not shown in the Design Explorer or Members List. The The forward slash character is not shown in the Design Explorer or Members List. The WORLD has a special name in

WORLD has a special name in PDMS,PDMS, Names cannot contain spaces and are case

Names cannot contain spaces and are case sensitive. For example, /E1302A is a differentsensitive. For example, /E1302A is a different name from /E1302a or /e1302A. Elements in a PDMS database are unique,

name from /E1302a or /e1302A. Elements in a PDMS database are unique, i.e. theyi.e. they cannot have the same name or

cannot have the same name or reference number.reference number.

5.2.2 TYPE 5.2.2 TYPE

This attribute refers to the specific type of element it is, e.g. EQUI is an Equipment This attribute refers to the specific type of element it is, e.g. EQUI is an Equipment type.

type.

5.2.3 LOCK 5.2.3 LOCK

The LOCK attribute determines if an element may be

The LOCK attribute determines if an element may be changed or not. If changed or not. If an element isan element is locked, its LOCK attribute is set to

locked, its LOCK attribute is set to the value TRUE, preventing it from being the value TRUE, preventing it from being modifiedmodified until unlocked.

until unlocked. By default, By default, LOCK is LOCK is false.false.

5.2.4 OWNER 5.2.4 OWNER

The different levels in

The different levels in the hierarchy are maintained by an the hierarchy are maintained by an Owner-Member relationship.Owner-Member relationship.

 An EQUI will have ZONE as its owner, while a

 An EQUI will have ZONE as its owner, while a CYLI might well be one of the EQUI’sCYLI might well be one of the EQUI’s members. The owner is that element which

members. The owner is that element which is directly related to the is directly related to the current element atcurrent element at the next level up in the hierarchy, as shown in

the next level up in the hierarchy, as shown in the diagram below:the diagram below:

A simple ownership structure A simple ownership structure

The element on the upper level is the Owner of those elements directly below it,

The element on the upper level is the Owner of those elements directly below it, e.g. thee.g. the equipment (EQUI) owns the primitive (CYLI). The l

equipment (EQUI) owns the primitive (CYLI). The lower level elements are Members of ower level elements are Members of  the owning element, e.g. the EQUI is a member of the ZONE.

the owning element, e.g. the EQUI is a member of the ZONE.

5.2.5 POSITION 5.2.5 POSITION

Many items in a database have a POSITION attribute which is the position of the Many items in a database have a POSITION attribute which is the position of the

element in relation to its owner. All primitives have a position attribute which relates to element in relation to its owner. All primitives have a position attribute which relates to its point of origin. As each primitive has a different Point of Origin

its point of origin. As each primitive has a different Point of Origin changing the positionchanging the position attribute will have the effect of moving the cylinder to some other position with its point attribute will have the effect of moving the cylinder to some other position with its point of origin positioned on the new co-ordinates.

of origin positioned on the new co-ordinates.

Point of Origin of a CYLI Point of Origin of a CYLI

5.2.6 ORIENTATION 5.2.6 ORIENTATION

By default, a cylinder is created in a vertical direction; that is, with one

By default, a cylinder is created in a vertical direction; that is, with one of its ends facingof its ends facing up. The orientation attribute allows this to be changed to any angle on any axis.

up. The orientation attribute allows this to be changed to any angle on any axis.

5.2.7 LEVEL 5.2.7 LEVEL

PDMS can produce different

PDMS can produce different of an item, depending on how it has beenof an item, depending on how it has been modelled and the representation levels used. The default level is 0 to 10 but levels can modelled and the representation levels used. The default level is 0 to 10 but levels can be set beyond this range if needed.

be set beyond this range if needed.

For example, steelwork profiles can be

For example, steelwork profiles can be represented by centreline (stick representation)represented by centreline (stick representation) only or by the full detail of the

only or by the full detail of the section profile. By manipulating level settings it is,section profile. By manipulating level settings it is, therefore, possible to have simple or

therefore, possible to have simple or complex representation of elements for Designcomplex representation of elements for Design display or Draft drawings.

display or Draft drawings.

5.2.8 OBSTRUCTION 5.2.8 OBSTRUCTION

The OBSTRUCTION attribute is used to declare whether an

The OBSTRUCTION attribute is used to declare whether an element is solid or element is solid or not.not.

Obstructions can be declared as Hard, Soft or

Obstructions can be declared as Hard, Soft or No Obstruction, depending on the value No Obstruction, depending on the value of of  the OBSTRUCTION attribute. The default value of 2 results in

the OBSTRUCTION attribute. The default value of 2 results in a Hard obstruction, 1a Hard obstruction, 1 results in a Soft obstruction (used

results in a Soft obstruction (used for walkways, maintenance access etc.) and 0 is for walkways, maintenance access etc.) and 0 is for Nofor No Obstruction (used to save computing time when elements are

Obstruction (used to save computing time when elements are enclosed in anotherenclosed in another element which acts as an

element which acts as an overall obstruction).overall obstruction).

5.2.9 HEIGHT 5.2.9 HEIGHT

The height of the cylinder.

The height of the cylinder.

5.2.10 DIAMETER 5.2.10 DIAMETER

The diameter of the cylinder.

The diameter of the cylinder.

5.3

5.3 UDAs UDAs (User (User Defined Defined Attributes) Attributes)

This type of attribute is defined and assigned to elements using the Lexicon module by This type of attribute is defined and assigned to elements using the Lexicon module by the System or Project Administrator. A 

the System or Project Administrator. A  is just like any is just like any other attribute but may beother attribute but may be specific to the company or the particular project. The setting of the UDA is up to the specific to the company or the particular project. The setting of the UDA is up to the user, although it may have been set to a default value. Changing this is the same as user, although it may have been set to a default value. Changing this is the same as with all other attributes. Their current

with all other attributes. Their current values may be found by querying values may be found by querying the itemsthe items attributes. A UDA can be recognised by the colon placed in front of it:

attributes. A UDA can be recognised by the colon placed in front of it:

(User Defined Attribute)  (User Defined Attribute)  (Normal Attribute) 

(Normal Attribute) 

In document PDMS Basics (Page 43-49)