AIRFLOW_VELOCITY_CTRL
Longitudinal air-velocity PI loop on a SIGNED setpoint, with the measurement resolved into the commanded direction and an open-loop fire fallback.
When to use it
Use AIRFLOW_VELOCITY_CTRL when a tunnel section's longitudinal air velocity must be held at a signed setpoint by a fan demand, and in fire mode at no less than the critical velocity in the commanded direction.
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 | — |
| FIRE_MODE | BOOL | — |
| VEL_SP | REAL | m/s |
| VEL_PV | REAL | m/s |
| VEL_OK | BOOL | — |
| CRIT_VEL | REAL | m/s |
| KP | REAL | %/(m/s) |
| TI | REAL | s |
| DB | REAL | m/s |
| DEM_MIN | REAL | % |
| DEM_MAX | REAL | % |
| RATE_PCT_S | REAL | %/s |
| FIRE_FALLBACK_PCT | REAL | % |
| REV_TMO | TIME | — |
| ACK | BOOL | — |
Outputs
| Port | Type | Unit |
|---|---|---|
| FAN_DEMAND | REAL | % |
| DIR | BOOL | — |
| SP_USED | REAL | m/s |
| ERR | REAL | m/s |
| AT_SP | BOOL | — |
| VALID | BOOL | — |
| ALM_VEL_FAULT | BOOL | — |
| ALM_REVERSED | BOOL | — |
| ALM_SP_BELOW_CRIT | BOOL | — |
| ALM_NO_DIR | BOOL | — |
| ALM_CFG_ERR | BOOL | — |
IEC 61499 event interface
EI INIT, REQ·EO INITO, CNF
Validation evidence
- Tests
- 12
- Simulated scans
- 423
- 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 AIRFLOW_VELOCITY_CTRL — free
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