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Alarms

QUBIQ implements tag alarming to ISA-18.2 / IEC-62682: the standard that exists because badly designed alarm systems have caused industrial accidents.

An alarm is attached to a tag. One tag can carry many alarms — Hi, HiHi, Lo, LoLo, Fault — each with its own condition, priority and message.

The lifecycle

The four alarm states: Normal, Active and unacknowledged, Acknowledged, and Cleared but never acknowledged, with the transitions between them.The four alarm states: Normal, Active and unacknowledged, Acknowledged, and Cleared but never acknowledged, with the transitions between them.
An alarm that cleared on its own still waits for a human — that is the Cleared state.
StateMeaning
NORMCondition not met, nothing outstanding
UNACKCondition met, awaiting acknowledgement
ACKCondition still met, operator has acknowledged
RTNUNCondition cleared, but was never acknowledged

RTNUN is the state that matters most and the one operators find least intuitive. A transient excursion that self-corrected still has to be seen — otherwise a repeating fault disappears before anyone notices it happened.

Priorities

PriorityUse for
criticalSafety, environmental release, production stop
highRequires prompt operator action
mediumRequires action this shift
lowInformational; action when convenient

Reserve critical. An alarm system where everything is critical is an alarm system operators learn to ignore, which is precisely the failure mode ISA-18.2 exists to prevent.

Events

Every transition is journalled:

EventMeaning
raisedThe alarm annunciated
ackAn operator acknowledged
rtnThe condition returned to normal
clearThe cycle fully closed (→ NORM)
shelveTemporarily shelved by an operator
suppressSuppressed indefinitely by design or logic
oosTaken out of service for maintenance
restoreSuppression released, back in service

Suppression: three distinct kinds

Being able to silence an alarm is necessary. Being unable to tell why it is silent is dangerous — so QUBIQ records the reason as part of the state.

KindDurationWhoUse for
ShelveTemporary, auto-released on expiryOperatorA known nuisance during a shift
Suppress by designIndefiniteEngineeringAn alarm that is meaningless in the current mode
Out of serviceIndefiniteMaintenanceEquipment deliberately down

A shelved alarm returns on its own. That is the whole point: it cannot be forgotten.

Operating alarms

Where alarms appear

SurfaceComponent
AnnunciatorAlarm Bell
Active list, and per-tag indicatorAlarm Event
HistoryAlarm Journal
Metrics / KPIsAlarm Performance
PipelinesThe Alarm node, subscribing to lifecycle events

The alarm widgets read the alarm system directly — no binding required — and respect the viewer's alarm permissions.

Notification

To send alarms somewhere — email, SMS, a webhook, a paging system — use a pipeline:

Alarm node (raised, priority: critical)
→ Python (format the message)
→ REST API (egress → your notification service)

The Alarm node filters by event type, priority and tag, and can attach the tag's static metadata to each event.

Pipeline nodes

Permissions

ActionPermission
See active alarms and the journalView alarms
Acknowledge, shelve, suppress, restoreAcknowledge alarms
Create/edit/delete alarm definitions and storage settingsManage alarms

Acknowledgement is deliberately separate from configuration: an operator acknowledges; an engineer defines.

Design principles

Before adding an alarm, answer four questions:

  1. Is it actionable? If nobody does anything differently, it is an event, not an alarm.
  2. What is the priority, honestly? Everything critical means nothing is.
  3. What delay and deadband? Nearly every chattering alarm is a missing on-delay or deadband.
  4. What does the message tell the operator to do? Put the response in the message text.

A well-rationalised plant produces a handful of alarms per operator per hour. A poorly rationalised one produces hundreds — and the operator stops reading them long before the one that mattered.

In this section

PageContents
Configuring alarmsModes, setpoints, deadband, delays, latching
Operating alarmsAcknowledging, shelving, the journal, metrics