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 | — |
IEC 61499 event interface
EI INIT, REQ·EO INITO, CNF
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
- Conforms to IEC 61499
Download ECONOMIZER_CTRL — free
Create a free Ri Tech account to download the block. You get the Structured Text body, the Rockwell Add-On Instruction (.L5X), the Schneider Control Expert DFB (.XDB), PLCopen XML, the IEC 61499 function block type (.fbt) and the datasheet.
Every block in the catalogue is free to download, in every format, with no purchase and no card. Browsing needs no account at all; downloading needs a signed-in one, so the block lands in your library and re-downloads whenever you need it.
Source is never published on this page. The implementation is released to a signed-in Ri Tech account — free of charge, but never anonymously.