CHILLER_PLANT_SEQ
Chiller plant staging on machine loading and chilled-water supply temperature, with anti-short-cycle protection in both directions; lead/lag rotation is NOT in this block.
When to use it
Use CHILLER_PLANT_SEQ when two or more equally sized chillers serve one chilled-water plant and the number of machines running has to follow the cooling load without cycling a compressor — and the run-hour rotation that decides WHICH machines those are is handled by the chiller start logic downstream, not here.
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 | — |
| COOL_REQ | BOOL | — |
| LOAD_TON | REAL | ton |
| LOAD_OK | BOOL | — |
| CHW_SUP | REAL | °C |
| CHW_OK | BOOL | — |
| CHW_SP | REAL | °C |
| N_CHILLERS | USINT | — |
| CHILLER_TON | REAL | ton |
| UP_PCT | REAL | % |
| DN_PCT | REAL | % |
| DB_K | REAL | K |
| UP_DLY | TIME | — |
| DN_DLY | TIME | — |
| MIN_STAGE_TIME | TIME | — |
| FTM_TMO | TIME | — |
| ACK | BOOL | — |
Outputs
| Port | Type | Unit |
|---|---|---|
| STAGE | USINT | — |
| CHILLERS_ON | USINT | — |
| NEXT_STAGE | BOOL | — |
| LOAD_PCT | REAL | % |
| VALID | BOOL | — |
| ALM_FAIL_TO_MAINTAIN | BOOL | — |
| ALM_SENSOR | BOOL | — |
| ALM_CFG_ERR | BOOL | — |
IEC 61499 event interface
EI INIT, REQ·EO INITO, CNF
Validation evidence
- Tests
- 9
- Simulated scans
- 884
- 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 CHILLER_PLANT_SEQ — free
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