AIRFLOW_CFM_MON
Airflow monitor with seeded first-order filter, delayed and latched minimum-flow alarm, percent-of-design and frozen-transmitter detection.
When to use it
Use AIRFLOW_CFM_MON when the air volume delivered by a CRAH, an air-handling unit or a containment supply has to be proven above a minimum before the load below it is considered cooled, and a stuck airflow transmitter must not be able to prove it.
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 | — |
| CFM_RAW | REAL | cfm |
| SENSOR_OK | BOOL | — |
| CFM_MIN | REAL | cfm |
| CFM_DESIGN | REAL | cfm |
| HYST_CFM | REAL | cfm |
| FILT_T | TIME | — |
| ALM_DLY | TIME | — |
| STUCK_BAND_CFM | REAL | cfm |
| STUCK_T | TIME | — |
| ACK | BOOL | — |
Outputs
| Port | Type | Unit |
|---|---|---|
| CFM | REAL | cfm |
| OK | BOOL | — |
| FLOW_PCT | REAL | % |
| LOW_FLOW | BOOL | — |
| ALM_LOW_FLOW | BOOL | — |
| ALM_STUCK | BOOL | — |
| ALM_SENSOR_FAULT | BOOL | — |
| VALID | BOOL | — |
IEC 61499 event interface
EI INIT, REQ·EO INITO, CNF
Validation evidence
- Tests
- 10
- Simulated scans
- 320
- 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_CFM_MON — free
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Source is never published on this page. The implementation is released to a signed-in Ri Tech account — free of charge, but never anonymously.