This simulator models a wet-pipe sprinkler riser waterflow switch: a flexible paddle deflected by imposed flow, a retard mechanism that requires the flow to stay above threshold for a set interval before the contact operates, and a panel that can keep an alarm latched even after flow stops. Adjust flow, threshold and retard, and see how brief transients are rejected while sustained flow is reported.
• Equipment laboratory tab: a real-time cutaway workbench of the wet sprinkler riser, flexible sensing paddle, retard mechanism, alarm microswitch, inspector-test branch, sprinkler and discharge path, and addressable monitor module, 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: a riser-flow slider (0–200 L/min), an illustrative flow-switch-threshold slider (20–60 L/min) and a retard-setting slider (0–90 s), plus Start trial, Stop equipment, Acknowledge and Reset alarm memory actions, a Pause/Advance 0.1 s/Advance 1 s time control with four playback speeds (real time to 1 minute per second), a live "what is happening" sequence readout, live metrics (riser flow, illustrated vane angle, continuous qualifying flow, time to contact, flow contact, panel alarm memory), and a switch-state token display. • Curves & measurements tab: a primary-measurements chart (riser flow) and a response/sequence chart (continuous timer, contact and panel memory), the underlying model equations, a snapshot-measurements readout and written model-scope notes. • Experiments tab: four guided trials (no flow, sustained test flow, sub-threshold flow, transient rejection) that pre-load the relevant flow and retard values and describe the expected response, a "Run model checks" built-in verification suite that checks the model with independent fresh instances without disturbing your current trial, and a timestamped event log with a trial-report export. • Learn & assess tab: lesson cards on establishing water movement, deflecting the vane, rejecting a short transient and reporting sustained flow, a knowledge-check quiz with reset, and a scope/references panel with a link to a sprinkler flow-switch technical reference document.
A wet-pipe sprinkler waterflow switch senses water movement in the riser mechanically: an opened sprinkler lets water flow, and a flexible paddle inserted in the pipe deflects in proportion to that flow. In this fixture, flow at or above the illustrative flow-switch threshold is treated as qualifying flow, and a continuous timer accumulates while qualifying flow persists.
The retard mechanism exists to reject brief, non-fire-related pressure transients — the timer only reaches the alarm microswitch's operating point once qualifying flow has been continuous for the full retard interval; if flow drops below threshold even briefly, the timer resets to zero rather than accumulating separate short pulses toward the same total. Once the contact operates, the panel can latch an alarm in memory that remains even after flow — and the flow contact itself — return to normal, which is why acknowledging or the contact restoring does not by itself clear the panel's alarm memory.
The live metrics and primary-measurements chart track riser flow directly, while the response/sequence chart pairs the continuous qualifying-flow timer against the flow-contact and panel-memory flags, so you can see the timer climbing toward the retard setting and the contact operating exactly when it reaches that value. The illustrated vane angle is a simple mechanical indication scaled from flow, not a manufacturer's calibration curve.
Acknowledging an alarm only records operator awareness — it does not stop the physical water flow or reset the panel's memory; Reset alarm memory requires the initiating condition to be restored first. The Run model checks button in the Experiments tab exercises the underlying threshold, retard-timer and contact/latch logic against independent fresh model instances so you can confirm the equations hold before trusting the displayed sequence. This is a representative educational sequence only — it is not a listed-device sensitivity specification, wiring design, commissioning procedure, or a pipe hydraulics or code-required alarm-timing calculation.
The retard mechanism requires flow to stay continuously at or above the illustrative threshold for the full retard interval before the contact operates, so that brief, non-fire-related pressure transients in the riser do not cause a false alarm.
The continuous qualifying-flow timer resets to zero. Separate short pulses of flow do not accumulate toward the same alarm — flow has to be continuously sustained above threshold for the whole selected retard interval.
No. In this fixture the flow contact can restore to normal once flow drops, but the panel keeps the alarm latched in memory. Acknowledgement records operator awareness, and Reset alarm memory requires the initiating condition to be restored first — they are separate operations.
The Run model checks button in the Experiments tab runs the threshold-qualification, retard-timer reset and contact/panel-latch logic against independent, freshly created model instances, confirming the teaching model behaves consistently without altering your current trial.