Engineering quantities (EQ-VOCAB)

Open-FDD defines a versioned engineering-quantity vocabulary for design / rated / TAB capacities that feed PyPI ECM tools. Telemetry and FDD math stay in Parquet / DataFusion; these records are model evidence, not historian samples.

Field Value
Vocab version ofdd_engineering_quantities_v1
Namespace urn:openfdd:ns#
Turtle vocab/ofdd_engineering_quantities_v1.ttl
JSON schema vocab/ofdd_engineering_quantities_v1.schema.json
Python open_fdd.ecm_engineering.eq_vocab (wheel copy is authoritative; Pages copy parity-tested)

Quantity record (required)

Each capacity property points at an EngineeringQuantity record with:

  • numeric_value (finite) + registered unit_code
  • quantity_kind (e.g. ElectricalPower vs ThermalPower)
  • value_basis (Design | Rated | TAB | Measured | Assumed)
  • source_type / optional locator + review_status

Do not treat thermal kW as electrical demand. Do not invent annual hours or ton-hours from nameplate alone.

Properties (v1)

ratedCoolingCapacity, ratedHeatingCapacity, ratedFuelInputPower, ratedElectricalInputPower, ratedShaftPower, designSupplyAirflow, designOutdoorAirflow, designWaterFlow, designExternalStaticPressure, designPumpHead, ratedCOP, ratedEER, ratedThermalEfficiency.