Point Dictionary: VFD

Variable frequency drive point dictionary. The VFD family’s rules are application-agnostic (fan, pump); the process-variable pair is deliberately untyped beyond ‘the controlled variable in its own units’ and marked provisional. Owning equipment: brick:Variable_Frequency_Drive (verified in Brick 1.4.4). ASHRAE 223 mappings were checked against local artifact 223p-1.0.0-ppr2.1.ttl, SHA-256 1f156f9938c0be430d2216e01e31bb183c438ba318d8d4a23d2f074ebcd6f573; this is a public-review artifact pin, not a claim of a later published release.

vfd_speed_cmd

VFD speed command (0-100%)

• 223P: QuantifiableActuatableProperty on the VFD via hasProperty
• QUDT unit: PERCENT

brick:Speed_Setpoint is an exact Brick 1.4.4 class, but Brick’s inherited Speed quantity does not list PERCENT as an applicable unit; the normalized percent binding is therefore provisional. ASHRAE 223 PPR2.1’s g36:FanWithVFD shape explicitly uses a QuantifiableActuatableProperty with quantity kind DimensionlessRatio for the drive speed command; this dictionary narrows that ratio to PERCENT.

vfd_speed

VFD speed feedback (0-100%)

• 223P: Sensor observes QuantifiableObservableProperty on the driven motor via hasProperty
• QUDT unit: PERCENT

brick:Motor_Speed_Sensor is an exact Brick 1.4.4 class and brick:Speed_Status is the drive-reported alternative, but Brick’s inherited Speed quantity does not list PERCENT as an applicable unit; the normalized percent binding is therefore provisional. Bind whichever the site trends, but note VFD-0001 diagnosis 5 (tachometer failure) argues for the drive-reported value where both exist. ASHRAE 223 represents the normalized feedback as a DimensionlessRatio QuantifiableObservableProperty in PERCENT.

vfd_process_value

Controlled process variable (pressure, flow, or temperature — the loop’s PV, in its own units)

Deliberately generic: the VFD family’s rules compare PV against setpoint in whatever unit the loop uses, and VFD-0002’s pv_error_threshold is set in those same units. Semantic tags belong on the application-specific point (duct static pressure, water differential pressure, …) that the host binds here.

vfd_process_sp

Setpoint for the controlled process variable (same units as vfd_process_value)

See vfd_process_value; the pair must be bound from the same loop in the same units.

vfd_enable_cmd

Final BAS command requesting VFD operation/control

• 223P: EnumeratedActuatableProperty on the VFD via hasProperty, with hasEnumerationKind Binary-OnOff

brick:VFD_Enable_Command is an exact Brick 1.4.4 class. Bind the final drive-level command downstream of schedule and normal equipment interlocks; a system request several sequence layers upstream is not equivalent. ASHRAE 223 represents the command as an EnumeratedActuatableProperty with s223:Binary-OnOff.

vfd_auto_status

True when the drive is accepting remote automatic control from the BAS/control loop

• 223P: EnumeratedObservableProperty on the VFD via hasProperty, with hasEnumerationKind Binary-Logical and hasAspect Aspect-OperatingMode; true denotes the deployment’s verified remote-auto state

brick:Manual_Auto_Status is exact in Brick 1.4.4 for manual-versus-automatic operation, but it does not by itself prove that ‘auto’ is remote BAS control rather than a drive-local automatic source; that deployment-specific narrowing keeps this canonical point provisional. Enabled and automatic are not equivalent. ASHRAE 223 uses a Binary-Logical EnumeratedObservableProperty with Aspect-OperatingMode whose true value must be mapped to the verified remote-auto state.

vfd_bypass_status

True while the motor is operating through a bypass path rather than regulated VFD output

• 223P: EnumeratedObservableProperty on the drive/bypass assembly via hasProperty, with hasEnumerationKind Binary-Logical and hasAspect Aspect-OperatingMode

Brick 1.4.4 has brick:Bypass_Command but no exact bypass-status class; using the command would confuse request with proof, so the Brick mapping is null. In ASHRAE 223 this is a Binary-Logical observable operating-mode property on the drive/bypass assembly; native bypass-contactor proof may instead be represented as Binary-OnOff, but the canonical binding still means confirmed active bypass, not a request. Approved emergency or maintenance bypass is an operating-state exclusion, not a different point meaning.