IfcDamper

IfcDamper

Definition from IAI: This class defines elements of a damper, which typically is used in an HVAC air distribution system to control or modulate the flow of air.

An IfcActuator can be either aggregated into the definition of the IfcDamper using the IfcRelAssemblesElements relationship, or referenced using the IfcRelConnectsElements objectified relationship.

HISTORY: New entity in IFC R2.0
ISSUES: See issues and change log for changes made in IFC R2x.

Geometry Use Definitions

The geometric representation of IfcDamper is given by the IfcProductDefinitionShape, allowing multiple geometric representations. Included are:

Local Placement

The use of local placement is defined at the supertype IfcDistributionFlowElement.

Standard Geometric Representation

The use of Standard Geometric Representations is defined at the supertype IfcDistributionFlowElement.

EXPRESS specification:

ENTITY IfcDamper

SUBTYPE OF (

IfcFlowController);

PredefinedType

IfcDamperTypeEnum;

FrameDepth

OPTIONAL IfcLengthMeasure;

SizingMethod

OPTIONAL IfcDamperSizingMethodEnum;

CloseOffRating

OPTIONAL IfcPressureMeasure;

LeakageAirFlowRate

OPTIONAL IfcVolumetricFlowRateMeasure;

PercentOpen

OPTIONAL IfcPositiveRatioMeasure;

WHERE

WR1

(PredefinedType <> IfcDamperTypeEnum.USERDEFINED) OR ((PredefinedType = IfcDamperTypeEnum.USERDEFINED) AND EXISTS(SELF\IfcObject.ObjectType)) ;

END_ENTITY;

Attribute definitions:

PredefinedType	:	Predefined generic types are specified in an Enumeration. A TypeDefinition is available for each generic type (as the required attributes differ). Use Type Definition corresponding to this generic type. Type Definitions Type driven PropertySets PreDefined Type Associated PropertySet FireDamper Pset_FireDamper SmokeDamper Pset_SmokeDamper FireSmokeDamper Pset_FireSmokeDamper BackdraftDamper Pset_BackdraftDamper ControlDamper Pset_ControlDamper Louver Pset_Louver UserDefined NotDefined
FrameDepth	:	The length (or depth) of the damper frame.
SizingMethod	:	Enumeration that identifies whether the damper is sized nominally or with exact measurements.
CloseOffRating	:	Close off rating.
LeakageAirFlowRate	:	Leakage air flow rate: the volume of air that still passes through a fully closed damper.
PercentOpen	:	Defines the percentage open position for the damper blades. This value varies for dampers under automatic control, but typically remain fixed for dampers used for balancing purposes.

Formal Propositions:

WR1

References (1):

Name

Type

Referred through

Express-G

IfcFlowController

Entity

Subtype

Diagram 1

Inheritance graph

ENTITY IfcDamper;

ENTITY IfcRoot;

GlobalId

IfcGloballyUniqueId;

OwnerHistory

IfcOwnerHistory;

Name

OPTIONAL IfcLabel;

Description

OPTIONAL IfcText;

ENTITY IfcObject;

ObjectType

OPTIONAL IfcLabel;

INVERSE

IsDefinedBy

SET OF IfcRelDefines FOR RelatedObjects;

HasAssociations

SET OF IfcRelAssociates FOR RelatedObjects;

HasAssignments

SET OF IfcRelAssigns FOR RelatedObjects;

Decomposes

SET OF IfcRelDecomposes FOR RelatedObjects;

IsDecomposedBy

SET [0:1] OF IfcRelDecomposes FOR RelatingObject;

ENTITY IfcProduct;

ObjectPlacement

OPTIONAL IfcObjectPlacement;

Representation

OPTIONAL IfcProductRepresentation;

INVERSE

ReferencedBy

SET OF IfcRelAssignsToProduct FOR RelatingProduct;

ENTITY IfcElement;

Tag

OPTIONAL IfcIdentifier;

INVERSE

ConnectedTo

SET OF IfcRelConnectsElements FOR RelatingElement;

ConnectedFrom

SET OF IfcRelConnectsElements FOR RelatedElement;

ContainedInStructure

SET [0:1] OF IfcRelContainedInSpatialStructure FOR RelatedElements;

ENTITY IfcDistributionFlowElement;

FlowElementType

IfcDistributionFlowElementTypeEnum;

INVERSE

HasControlElements

SET [0:1] OF IfcRelFlowControlElements FOR RelatingFlowElement;

ENTITY IfcDamper;

PredefinedType

IfcDamperTypeEnum;

FrameDepth

OPTIONAL IfcLengthMeasure;

SizingMethod

OPTIONAL IfcDamperSizingMethodEnum;

CloseOffRating

OPTIONAL IfcPressureMeasure;

LeakageAirFlowRate

OPTIONAL IfcVolumetricFlowRateMeasure;

PercentOpen

OPTIONAL IfcPositiveRatioMeasure;

END_ENTITY;