FIRE_VENT_SEQ
Fire-ventilation sequence: resolves the smoke-control direction from the evacuation direction, sequences dampers before fans, and confirms critical velocity.
When to use it
Use FIRE_VENT_SEQ when a longitudinally ventilated tunnel has a commanded fire mode, and the ventilation must be driven to at least the critical velocity in the one direction that keeps the evacuation route clear of smoke.
Interface
The published port signature. This is the whole of what the block exposes to your program — the implementation body is not shown here and ships with the download.
Inputs
| Port | Type | Unit |
|---|---|---|
| ENABLE | BOOL | — |
| ACTIVATE | BOOL | — |
| STOP_CMD | BOOL | — |
| FIRE_ZONE | USINT | — |
| N_ZONES | USINT | — |
| EVAC_DIR | BOOL | — |
| CRIT_VEL | REAL | m/s |
| DESIGN_VEL | REAL | m/s |
| VEL_PV | REAL | m/s |
| VEL_OK | BOOL | — |
| DAMPER_DLY | TIME | — |
| CONFIRM_TMO | TIME | — |
| VEL_TOL | REAL | m/s |
| DIR_CONF_TM | TIME | — |
| ACK | BOOL | — |
Outputs
| Port | Type | Unit |
|---|---|---|
| FAN_PATTERN | USINT | — |
| AIRFLOW_SP | REAL | m/s |
| AIR_DIR | BOOL | — |
| STEP | USINT | — |
| RUNNING | BOOL | — |
| CRIT_VEL_MET | BOOL | — |
| VALID | BOOL | — |
| ALM_BACKLAYER | BOOL | — |
| ALM_ZONE_INVALID | BOOL | — |
| ALM_VEL_FAULT | BOOL | — |
| ALM_ISOLATED | BOOL | — |
| ALM_DIR_CHANGED | BOOL | — |
| ALM_STOP_HELD | BOOL | — |
| ALM_CFG_ERR | BOOL | — |
IEC 61499 event interface
EI INIT, REQ·EO INITO, CNF
Supervised control write
FIRE_VENT_SEQ commands a real actuator. It is written to sit underneath your own interlock, permissive and protection logic — not to replace it. Commission it as you would any control block you wrote yourself.
Validation evidence
- Tests
- 14
- Simulated scans
- 277
- Simulator
- v0.1.0
Complete IEC 61131-3 implementation with a published test suite that runs on the vplant simulator. The counts above are that suite, executed on this build.
- Conforms to IEC 61131-3
- Conforms to IEC 61499
Download FIRE_VENT_SEQ — free
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