CELL_DENSITY_EST
Viable-cell-density soft sensor from a capacitance probe, cross-checked against respiration, with a logarithmic growth rate.
When to use it
Use CELL_DENSITY_EST when a capacitance (dielectric) probe is fitted in a bioreactor and viable cell density is wanted continuously between off-line counts, with a second, independent estimate available from the off-gas oxygen uptake.
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 | — |
| CAP_PF | REAL | pF/cm |
| CAP_OK | BOOL | — |
| OUR | REAL | mmol/L/h |
| OUR_OK | BOOL | — |
| CAP_OFFSET | REAL | pF/cm |
| CAP_GAIN | REAL | 1e6cells/mL per pF/cm |
| QO2 | REAL | mmol/1e9cells/h |
| FILT_TAU | REAL | s |
| DEV_PCT | REAL | % |
| CONF_T | TIME | — |
| SAMPLE_T | TIME | — |
| ACK | BOOL | — |
Outputs
| Port | Type | Unit |
|---|---|---|
| VCD_EST | REAL | 1e6cells/mL |
| VCD_CAP | REAL | 1e6cells/mL |
| VCD_OUR | REAL | 1e6cells/mL |
| MU | REAL | 1/h |
| MU_VALID | BOOL | — |
| SOURCE | INT | — |
| VALID | BOOL | — |
| ALM_CAP_FAULT | BOOL | — |
| ALM_CAP_BLANK | BOOL | — |
| ALM_DISAGREE | BOOL | — |
| ALM_CFG_ERR | BOOL | — |
IEC 61499 event interface
EI INIT, REQ·EO INITO, CNF
Validation evidence
- Tests
- 8
- Simulated scans
- 551
- 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 CELL_DENSITY_EST — free
Create a free Ri Tech account to download the block. You get the Structured Text body, the Rockwell Add-On Instruction (.L5X), the Schneider Control Expert DFB (.XDB), PLCopen XML, the IEC 61499 function block type (.fbt) and the datasheet.
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Source is never published on this page. The implementation is released to a signed-in Ri Tech account — free of charge, but never anonymously.