The Echonet ontology represents Echonet device objects and their properties. A Device defines one or more DeviceObject. Device objects represent mechanical functions of a device and aim at facilitating controls and status verification through communications between devices. There are general properties applicable to any device object, such as hasOperationStatus. These general properties are defined as subproperties of the hasDeviceObjectProperty property.
There are 7 groups of device objects, namely AirConditionerRelatedDevice, AudiovisualRelatedDevice, CookingHouseholdRelatedDevice, HealthRelatedDevice, HousingFacilitiesRelatedDevice, ManagementOperationRelatedDevice and SensorRelatedDevice. Each group has a corresponding code (hasGroupCode property) and is characterized by the hasOperationStatus property, which indicates whether the function native to this group of objects is operating or not (ON/OFF). The CodeList class defines enumerations used to represent admitted values for some properties, for example, the OperationStatus class defines the instances On and Off as admitted values for the hasOperationStatus property.
Each of the 7 groups mentioned above is further refined in device object subclasses with a specific code (hasClassCode property). For example, the AirConditionerRelatedDevice group includes the AirCleaner, Dehumidifier, ElectricHeater, and HomeAirConditioner classes, among others. Specific properties that characterize a certain device class, but not any device object, are defined as subproperties of the hasClassSpecificProperty property. For example, the hasOperationModeSetting property characterizes the HomeAirConditioner class.
- The general properties applicable to any device object, such as hasOperationStatus are defined globally under the hasDeviceObjectProperty property. The amount of DeviceObject classes was such that it was not possible to restrict (the cardinality of) these properties for all classes. For the future it is advised to restrict these properties locally at the level of each DeviceObject subclass.
- The amount of hasClassSpecificProperty properties specific to device classes, but not applicable to any device object, was such that it was not possible to define them all. However, we have defined three properties (hasDetectionThresholdLevel, hasOpenCloseSetting, and hasOperationModeSetting) that should be used as example to further populate the hasClassSpecificProperty according to the ECHONET Device Objects specification.