This simulator traces the full event path from an addressed field detector to a fire alarm control panel (FACP): a supervised signaling line circuit (SLC) communication pair, a receiver daughterboard that samples addressed messages, a panel processor that applies an illustrative processing delay before qualifying the event, a display that latches alarm memory, and a notification-command relay. Activate the detector, open the communication path, or slow the message sampling period to see how each stage changes what the panel receives and does.
• Equipment laboratory tab: a real-time cutaway workbench of the addressed initiating detector, the supervised communication pair, the SLC receiver daughterboard, the panel processor, the FACP display and LEDs, the notification-command output relay, and standby-battery context (shown for panel architecture, not modeled for capacity), with Home view, Focus selected part, Show full enclosure / cutaway, Exploded view, Auto rotate and Expand camera controls, a numbered clickable component list with callouts, and a labels toggle. • Experiment controls: an activate-detector-input checkbox, an open-communication-path fault checkbox, a message sampling period slider (0.1–2 s) and an illustrative panel processing delay slider (0.2–3 s), plus Start trial, Stop equipment, Acknowledge, Silence audible outputs and Reset alarm memory actions, a Pause/Advance 0.1 s/Advance 1 s time control with four playback speeds, a live sequence readout, and live metrics (field input, received alarm state, continuous event-processing timer, panel alarm memory, audible notification command, received-message count). • Curves & measurements tab: a primary-measurements chart plotting field input, received state and latched alarm together, a response chart plotting the processing timer against the audible notification command, the underlying model equations, a snapshot-measurements readout and written model-scope notes. • Experiments tab: four guided trials (detector alarm, broken communication path, slow polling, and a memory exercise showing alarm memory persists after the field input clears), a "Run model checks" built-in verification suite using independent fresh model instances, and a timestamped event log with a trial-report export. • Learn & assess tab: lesson cards on activating at the field, delivering an address, processing and latching the event, and the distinct roles of acknowledge, silence and reset, a knowledge-check quiz with reset, and a scope/references panel linking to an SLC installation-guide technical reference document.
A field detector's input changes locally the instant it activates, but the panel does not learn about it instantly — the addressed message is only delivered on the next sampled poll of the supervised communication pair, at the interval set by the message sampling period. If the communication path is open, that delivery never happens: the panel reports a supervisory trouble condition rather than receiving the alarm event at all, because an open circuit on its own is not evidence of fire.
Once a message is received, the panel processor applies an illustrative processing delay before the event qualifies and alarm memory latches. From that point, the notification-command relay drives the audible output as long as alarm memory is set and the output has not been silenced — acknowledging the alarm only marks operator awareness, while silence removes the audible command without touching alarm memory, and reset is blocked while the field input remains active.
The primary-measurements chart lines up field input, received state and latched alarm so you can see the delay each stage adds — the gap between the field-input step and the received-state step directly reflects the message sampling period, and the gap between received and latched reflects the panel processing delay. The response chart isolates the processing timer against the notification command so you can confirm the panel only commands the audible output after processing completes and while alarm memory is set and not silenced.
The Run model checks button in the Experiments tab exercises the sampling, processing-delay and latch-and-silence logic against independent fresh model instances. This is a representative educational event-path sequence, not a listed-device specification, wiring design or commissioning procedure — the deterministic message timing and the illustrative processing delay are teaching fixtures, not an actual panel alarm-verification feature or a permissible field delay setting from any manufacturer's documentation.
The detector's addressed message is only delivered on the next sampled poll of the supervised communication pair — the message sampling period sets how much latency that adds before the panel receives the event, which the Slow polling experiment demonstrates directly.
An open communication path prevents the addressed message from ever being delivered, so the panel indicates a trouble condition instead of receiving the alarm. Trouble reports impaired system operation and is treated as distinct from a fire alarm.
No. Acknowledgement only records operator awareness, and Silence audible outputs only removes the audible notification command — alarm memory persists in both cases and can only be cleared with Reset alarm memory, which is itself blocked while the field input remains active.
The Run model checks button in the Experiments tab runs the message-sampling, panel processing-delay, and alarm-latch/notification logic against independent, freshly created model instances, confirming the teaching model behaves consistently without altering your current trial.