SRT_WAS_CTRL
Sludge-age control by solids mass balance — computes the waste-activated-sludge flow that holds the target SRT, rate-limited, with an actual-SRT readback.
When to use it
Use SRT_WAS_CTRL when an activated-sludge plant wastes sludge to hold a target solids retention time, the mixed-liquor and waste solids concentrations are measured, and the wasting rate is to be computed rather than set by hand.
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 | — |
| MLSS | REAL | mg/L |
| MLSS_OK | BOOL | — |
| VOLUME_M3 | REAL | m3 |
| SRT_SP_D | REAL | d |
| WAS_TSS | REAL | mg/L |
| WAS_TSS_OK | BOOL | — |
| EFF_FLOW | REAL | m3/h |
| EFF_TSS | REAL | mg/L |
| WAS_FLOW_MEAS | REAL | m3/h |
| WAS_MEAS_OK | BOOL | — |
| WAS_MIN | REAL | m3/h |
| WAS_MAX | REAL | m3/h |
| RATE_LIM | REAL | m3/h/h |
| WASTE_INHIBIT | BOOL | — |
| SRT_DEV_D | REAL | d |
| SRT_DEV_T | TIME | — |
| WAS_PROVE_PCT | REAL | % |
| WAS_FAIL_T | TIME | — |
| ACK | BOOL | — |
Outputs
| Port | Type | Unit |
|---|---|---|
| WAS_FLOW | REAL | m3/h |
| WAS_MASS_KG_D | REAL | kg/d |
| INVENTORY_KG | REAL | kg |
| SRT_ACTUAL_D | REAL | d |
| SRT_VALID | BOOL | — |
| WASTING | BOOL | — |
| VALID | BOOL | — |
| AT_MAX | BOOL | — |
| ALM_MEAS_FAULT | BOOL | — |
| ALM_SRT_DEV | BOOL | — |
| ALM_WAS_NO_FLOW | BOOL | — |
| ALM_CFG_ERR | BOOL | — |
IEC 61499 event interface
EI INIT, REQ·EO INITO, CNF
Validation evidence
- Tests
- 9
- Simulated scans
- 235
- 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 SRT_WAS_CTRL — free
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