SCADA · Schema

ScadaAlarm

Schema for a SCADA alarm event triggered when a tag value crosses a configured threshold

Critical InfrastructureICSIndustrial AutomationIndustrial IoTOT SecuritySCADA

Properties

Name	Type	Description
alarmId	string	Unique identifier for the alarm instance
alarmName	string	Name or label of the alarm
tagId	string	Tag ID that triggered the alarm
alarmType	string	Type of alarm condition
priority	integer	Alarm priority level (1=Critical, 2=High, 3=Medium, 4=Low)
state	string	Current state of the alarm
activeTimestamp	string	ISO 8601 timestamp when the alarm became active
acknowledgedTimestamp	string	ISO 8601 timestamp when the alarm was acknowledged by an operator
clearedTimestamp	string	ISO 8601 timestamp when the alarm condition cleared
triggerValue	number	Tag value at the time the alarm was triggered
limitValue	number	Alarm limit that was exceeded
engineeringUnits	string	Engineering units of the trigger value
message	string	Human-readable alarm message displayed to operators
acknowledgedBy	string	Username of the operator who acknowledged the alarm
processArea	string	Process area where the alarm occurred
notes	string	Operator notes added during alarm acknowledgment

View JSON Schema on GitHub

JSON Schema

{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://raw.githubusercontent.com/api-evangelist/scada/main/json-schema/scada-alarm-schema.json",
  "title": "ScadaAlarm",
  "description": "Schema for a SCADA alarm event triggered when a tag value crosses a configured threshold",
  "type": "object",
  "properties": {
    "alarmId": {
      "type": "string",
      "description": "Unique identifier for the alarm instance",
      "example": "ALM-2026-05-02-001"
    },
    "alarmName": {
      "type": "string",
      "description": "Name or label of the alarm",
      "example": "Reactor Inlet Pressure High-High"
    },
    "tagId": {
      "type": "string",
      "description": "Tag ID that triggered the alarm",
      "example": "PLANT1.AREA2.PV_101"
    },
    "alarmType": {
      "type": "string",
      "description": "Type of alarm condition",
      "enum": ["High-High", "High", "Low", "Low-Low", "Rate-of-Change", "Deviation", "Discrete", "Communication"],
      "example": "High-High"
    },
    "priority": {
      "type": "integer",
      "description": "Alarm priority level (1=Critical, 2=High, 3=Medium, 4=Low)",
      "minimum": 1,
      "maximum": 4,
      "example": 1
    },
    "state": {
      "type": "string",
      "description": "Current state of the alarm",
      "enum": ["Active", "Acknowledged", "Returned-to-Normal", "Shelved"],
      "example": "Active"
    },
    "activeTimestamp": {
      "type": "string",
      "format": "date-time",
      "description": "ISO 8601 timestamp when the alarm became active",
      "example": "2026-05-02T14:35:00.000Z"
    },
    "acknowledgedTimestamp": {
      "type": "string",
      "format": "date-time",
      "description": "ISO 8601 timestamp when the alarm was acknowledged by an operator"
    },
    "clearedTimestamp": {
      "type": "string",
      "format": "date-time",
      "description": "ISO 8601 timestamp when the alarm condition cleared"
    },
    "triggerValue": {
      "type": "number",
      "description": "Tag value at the time the alarm was triggered",
      "example": 185.3
    },
    "limitValue": {
      "type": "number",
      "description": "Alarm limit that was exceeded",
      "example": 180.0
    },
    "engineeringUnits": {
      "type": "string",
      "description": "Engineering units of the trigger value",
      "example": "PSI"
    },
    "message": {
      "type": "string",
      "description": "Human-readable alarm message displayed to operators",
      "example": "CRITICAL: Reactor inlet pressure PV-101 exceeded 180 PSI limit"
    },
    "acknowledgedBy": {
      "type": "string",
      "description": "Username of the operator who acknowledged the alarm"
    },
    "processArea": {
      "type": "string",
      "description": "Process area where the alarm occurred",
      "example": "Reactor Section"
    },
    "notes": {
      "type": "string",
      "description": "Operator notes added during alarm acknowledgment"
    }
  },
  "required": ["alarmId", "tagId", "alarmType", "priority", "state", "activeTimestamp", "message"],
  "additionalProperties": false
}