{
  "@context": {
    "@version": 1.1,
    "scada": "https://schema.scada.example.com/ontology#",
    "schema": "https://schema.org/",
    "xsd": "http://www.w3.org/2001/XMLSchema#",
    "ssn": "http://www.w3.org/ns/ssn/",
    "sosa": "http://www.w3.org/ns/sosa/",
    "iot": "http://iotschema.org/",

    "ScadaSystem": {
      "@id": "scada:ScadaSystem",
      "@type": "@id",
      "comment": "A Supervisory Control and Data Acquisition system"
    },
    "PLCDevice": {
      "@id": "scada:PLCDevice",
      "@type": "@id",
      "comment": "A Programmable Logic Controller (PLC) connected to the SCADA network"
    },
    "Tag": {
      "@id": "scada:Tag",
      "@type": "@id",
      "comment": "A SCADA data point representing a sensor, setpoint, or control variable"
    },
    "Alarm": {
      "@id": "scada:Alarm",
      "@type": "@id",
      "comment": "A SCADA alarm triggered when a tag value crosses a threshold"
    },
    "Historian": {
      "@id": "scada:Historian",
      "@type": "@id",
      "comment": "A time-series database that stores historical process data from SCADA"
    },
    "ProcessArea": {
      "@id": "scada:ProcessArea",
      "@type": "@id",
      "comment": "A logical grouping of equipment within a SCADA system"
    },
    "HMI": {
      "@id": "scada:HMI",
      "@type": "@id",
      "comment": "Human-Machine Interface for operator visualization and control"
    },
    "RTU": {
      "@id": "scada:RTU",
      "@type": "@id",
      "comment": "Remote Terminal Unit - a field device that collects data from sensors"
    },
    "Sensor": {
      "@id": "sosa:Sensor",
      "@type": "@id",
      "comment": "A physical device measuring an industrial process variable"
    },
    "Observation": {
      "@id": "sosa:Observation",
      "@type": "@id",
      "comment": "A measurement reading from a sensor at a specific time"
    },

    "tagName": {
      "@id": "scada:tagName",
      "@type": "xsd:string"
    },
    "tagValue": {
      "@id": "scada:tagValue"
    },
    "tagDataType": {
      "@id": "scada:tagDataType",
      "@type": "xsd:string"
    },
    "timestamp": {
      "@id": "scada:timestamp",
      "@type": "xsd:dateTime"
    },
    "quality": {
      "@id": "scada:quality",
      "@type": "xsd:string"
    },
    "alarmState": {
      "@id": "scada:alarmState",
      "@type": "xsd:string"
    },
    "alarmPriority": {
      "@id": "scada:alarmPriority",
      "@type": "xsd:integer"
    },
    "alarmMessage": {
      "@id": "scada:alarmMessage",
      "@type": "xsd:string"
    },
    "engineeringUnits": {
      "@id": "scada:engineeringUnits",
      "@type": "xsd:string"
    },
    "highHighLimit": {
      "@id": "scada:highHighLimit",
      "@type": "xsd:decimal"
    },
    "highLimit": {
      "@id": "scada:highLimit",
      "@type": "xsd:decimal"
    },
    "lowLimit": {
      "@id": "scada:lowLimit",
      "@type": "xsd:decimal"
    },
    "lowLowLimit": {
      "@id": "scada:lowLowLimit",
      "@type": "xsd:decimal"
    },

    "Device": "schema:Device",
    "name": "schema:name",
    "description": "schema:description",
    "identifier": "schema:identifier",
    "dateCreated": "schema:dateCreated",
    "dateModified": "schema:dateModified"
  }
}