ECONOMIZER_CTRL
Water-side economiser changeover on outdoor wet-bulb margin, with an integrated partial band, minimum dwell and line-up proving.
When to use it
Use ECONOMIZER_CTRL when a chilled-water plant can make some or all of its cooling through a plate heat exchanger from the cooling towers, and the decision to change over must be taken on outdoor wet bulb without cycling the plant across the threshold.
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 | — |
| OAT_WB | REAL | degC |
| WB_OK | BOOL | — |
| CWS_SP | REAL | degC |
| MARGIN | REAL | K |
| MARGIN_FLOOR | REAL | K |
| PARTIAL_BAND | REAL | K |
| HYST | REAL | K |
| MIN_MODE_TIME | TIME | — |
| HX_AVAIL | BOOL | — |
| CO_PROVEN | BOOL | — |
| PROVE_TMO | TIME | — |
| PULSE_T | TIME | — |
| ACK | BOOL | — |
Outputs
| Port | Type | Unit |
|---|---|---|
| FREE_COOL | BOOL | — |
| MODE | USINT | — |
| CHANGEOVER | BOOL | — |
| WB_MARGIN | REAL | K |
| ALM_WB_FAULT | BOOL | — |
| ALM_CO_FAIL | BOOL | — |
| ALM_HX_UNAVAIL | BOOL | — |
| ALM_CFG_ERR | BOOL | — |
Validation evidence
- Tests
- 7
- Simulated scans
- 339
- 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 ECONOMIZER_CTRL — free
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