DELTA_T_MON
Rack and CRAH air-side delta-T monitor: low-delta bypass syndrome, latched airflow loss, and a reversed-sensor check.
When to use it
Use DELTA_T_MON when supply and return air temperatures are measured across a CRAH or a rack row and the site needs to know whether the air is doing its job — low delta-T meaning bypass or recirculation, high delta-T meaning the airflow has gone.
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 |
|---|---|---|
| T_SUPPLY | REAL | degC |
| T_RETURN | REAL | degC |
| T_OK | BOOL | — |
| DT_MIN | REAL | K |
| DT_MAX | REAL | K |
| HYST_K | REAL | K |
| CONFIRM | TIME | — |
| REV_LIMIT | REAL | K |
| ACK | BOOL | — |
Outputs
| Port | Type | Unit |
|---|---|---|
| DT | REAL | K |
| LOW_DT | BOOL | — |
| HIGH_DT | BOOL | — |
| VALID | BOOL | — |
| ALM_AIRFLOW_LOSS | BOOL | — |
| ALM_SENSOR_REV | BOOL | — |
| ALM_T_FAULT | BOOL | — |
| ALM_CFG_ERR | BOOL | — |
Validation evidence
- Tests
- 7
- Simulated scans
- 187
- 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
Download DELTA_T_MON — free
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