DO_CASCADE_CTRL
Dissolved-oxygen cascade splitting one demand across agitation, then gas flow, then oxygen enrichment.
When to use it
Use DO_CASCADE_CTRL when a bioreactor holds dissolved oxygen with more than one actuator — impeller speed, total sparge rate and an O2 mass-flow controller — and the order in which those actuators are recruited is a process decision that has to be enforced in the controller.
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 | — |
| DO_PV | REAL | % |
| DO_OK | BOOL | — |
| DO_SP | REAL | % |
| KP | REAL | %/% |
| TI | REAL | s |
| AGIT_END_PCT | REAL | % |
| GAS_END_PCT | REAL | % |
| AGIT_MAX | REAL | % |
| GAS_MAX | REAL | % |
| O2_MAX | REAL | % |
| FAIL_DMD_PCT | REAL | % |
| DO_LO_PCT | REAL | % |
| DO_LO_TMO | TIME | — |
| ACK | BOOL | — |
Outputs
| Port | Type | Unit |
|---|---|---|
| AGIT_BIAS | REAL | % |
| GAS_BIAS | REAL | % |
| O2_BIAS | REAL | % |
| DEMAND_PCT | REAL | % |
| O2_ACTIVE | BOOL | — |
| VALID | BOOL | — |
| ALM_DO_LOW | BOOL | — |
| ALM_DO_FAULT | BOOL | — |
| ALM_SAT | BOOL | — |
| ALM_CFG_ERR | BOOL | — |
IEC 61499 event interface
EI INIT, REQ·EO INITO, CNF
Validation evidence
- Tests
- 8
- Simulated scans
- 89
- 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 DO_CASCADE_CTRL — free
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