COOLING_TOWER_SEQ
Cooling-tower cell staging and fan-speed control on a condenser-water setpoint reset toward the wet bulb.
When to use it
Use COOLING_TOWER_SEQ when one or more cooling-tower cells with variable-speed fans reject condenser heat, and the condenser-water supply temperature has to be held at a setpoint that follows the wet bulb.
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 | — |
| CW_SUP | REAL | °C |
| CW_OK | BOOL | — |
| CW_SP | REAL | °C |
| WB_TEMP | REAL | °C |
| WB_OK | BOOL | — |
| WB_RESET | BOOL | — |
| APPROACH_K | REAL | K |
| SP_MIN | REAL | °C |
| N_CELLS | USINT | — |
| KP | REAL | %/K |
| TI | TIME | — |
| FAN_MIN_PCT | REAL | % |
| FAN_OFF_DB | REAL | K |
| UP_PCT | REAL | % |
| DN_PCT | REAL | % |
| UP_DLY | TIME | — |
| DN_DLY | TIME | — |
| MIN_STAGE_TIME | TIME | — |
| FAN_FAIL_PCT | REAL | % |
| HI_DB | REAL | K |
| HI_TMO | TIME | — |
| ACK | BOOL | — |
Outputs
| Port | Type | Unit |
|---|---|---|
| CELLS_ON | USINT | — |
| FAN_SPEED | REAL | % |
| CW_SP_ACT | REAL | °C |
| VALID | BOOL | — |
| ALM_CW_HIGH | BOOL | — |
| ALM_SENSOR | BOOL | — |
| ALM_CFG_ERR | BOOL | — |
IEC 61499 event interface
EI INIT, REQ·EO INITO, CNF
Validation evidence
- Tests
- 11
- Simulated scans
- 841
- 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 COOLING_TOWER_SEQ — free
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