COOLING_TOWER_CTRL
Cooling-tower cell staging on condenser-water temperature with equal-speed sharing across running cells and a low-limit cut-out.
When to use it
Use COOLING_TOWER_CTRL when a multi-cell cooling tower with variable-speed fans holds condenser-water supply temperature for a chiller plant, and the condenser water must not be driven below the chillers' minimum entering temperature.
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 | — |
| CWT_PV | REAL | degC |
| CWT_OK | BOOL | — |
| CWT_SP | REAL | degC |
| N_CELLS | USINT | — |
| KP | REAL | %/K |
| TI | REAL | s |
| SPD_MIN | REAL | % |
| LOW_LIMIT | REAL | degC |
| UP_HYST | REAL | cells |
| DN_HYST | REAL | cells |
| STAGE_DLY | TIME | — |
| FAIL_FAN_PCT | REAL | % |
| HI_DEV | REAL | K |
| HI_TMO | TIME | — |
| ACK | BOOL | — |
Outputs
| Port | Type | Unit |
|---|---|---|
| FANS_ON | USINT | — |
| SPEED_PCT | REAL | % |
| DEMAND_PCT | REAL | % |
| ALM_CWT_FAULT | BOOL | — |
| ALM_LOW_CWT | BOOL | — |
| ALM_HIGH_CWT | BOOL | — |
| ALM_CFG_ERR | BOOL | — |
Validation evidence
- Tests
- 7
- Simulated scans
- 312
- 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 COOLING_TOWER_CTRL — free
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