FILTER_CTRL
Gravity filter constant-rate control with a three-criterion backwash request and a latched turbidity-breakthrough trip.
When to use it
Use FILTER_CTRL when a gravity (rapid sand or dual-media) filter is held at a constant filtration rate by a modulating effluent rate-control valve, and its backwash has to be requested on headloss, on individual-filter effluent turbidity, or on elapsed run time.
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 | — |
| RATE_SP | REAL | m3/h |
| FLOW | REAL | m3/h |
| FLOW_OK | BOOL | — |
| HEADLOSS | REAL | m |
| HL_OK | BOOL | — |
| HL_MAX | REAL | m |
| NTU_EFF | REAL | NTU |
| NTU_OK | BOOL | — |
| NTU_MAX | REAL | NTU |
| NTU_TRIP | REAL | NTU |
| NTU_PERSIST_T | TIME | — |
| NTU_TRIP_T | TIME | — |
| RUNTIME_H | REAL | h |
| RUNTIME_LIMIT_H | REAL | h |
| KP | REAL | %/(m3/h) |
| TI_S | REAL | s |
| VALVE_MIN_PCT | REAL | % |
| VALVE_MAX_PCT | REAL | % |
| BW_ACTIVE | BOOL | — |
| BW_DONE | BOOL | — |
| ACK | BOOL | — |
Outputs
| Port | Type | Unit |
|---|---|---|
| VALVE_PCT | REAL | % |
| BW_REQ | BOOL | — |
| REQ_BY_HL | BOOL | — |
| REQ_BY_NTU | BOOL | — |
| REQ_BY_TIME | BOOL | — |
| FILTER_AVAIL | BOOL | — |
| LOAD_PCT | REAL | % |
| RATE_ERR | REAL | m3/h |
| ALM_TURB_BREAK | BOOL | — |
| ALM_HL_HIGH | BOOL | — |
| ALM_FLOW_FAULT | BOOL | — |
| ALM_HL_FAULT | BOOL | — |
| ALM_NTU_FAULT | BOOL | — |
| ALM_NO_CRITERION | BOOL | — |
| ALM_CFG_ERR | BOOL | — |
IEC 61499 event interface
EI INIT, REQ·EO INITO, CNF
Validation evidence
- Tests
- 10
- Simulated scans
- 542
- 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 FILTER_CTRL — free
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