Appearance
Wastewater Pumping Station (Engineered Unit)
A wet well with submersible pumps on a common rising main — the first engineered unit, and the one whose generated content is most complete.
Which simulation? Running this unit uses the client-side, PLC-style scan simulation in your browser, not the server-side biokinetic process simulation. See Which "simulation" this section is about.
| Slug | ww-pumping-station |
| Name in the library | Wastewater Pumping Station (Engineered Unit) |
| Category | Process Units/engineered |
| Seeded | version 0.6.0, maturity published |
| Interface points | 3 — inlet, outlet, signals |
| Asked on drop | 9 for a new station, 14 for an existing one |
| Editable setpoints | 16 |
| Fault catalogue | 13 cases, filtered to what is fitted |
What it models
A wastewater pumping station: a wet well, one to six submersible pumps with up to two held as standby, a common rising main to a receiving chamber, and control panel CP-01.
The drawing it generates carries the wet well, the pumps and their drives, the non-return and isolation valve each branch's fittings call for, the level transmitter LT-101, the high-high and low-low floats LSHH / LSLL, the flow meter FT-101, the air valve, the emergency storage tank and the panel. Tags take their leading digit from the station's area number, so a second station on the same drawing is LT-201, P-201, CP-02 and does not collide.
The plant model integrated during a run is the wet well's water balance — inflow against what the running pumps deliver through the rising main at the head the system curve gives — together with the instruments that read it (including the possibility that they read it wrongly) and the pumps' mechanical state.
Key parameters
Asked on drop
Nine always, and five more when the station is an existing one — the figures you would survey on an asset that is already there rather than derive for one that is not.
| Parameter | Unit | Type | Asked |
|---|---|---|---|
| Design basis | — | new / existing | always |
| Dry weather flow | l/s | number | always |
| Design peak flow | l/s | number | always |
| Static head | m | number | always |
| Rising main length | m | number | always |
| Pumps installed | count | 1–6 | always |
| Pumps held as standby | count | 0–2 | always |
| Drive type | — | variable-speed drive / direct on line | always |
| Control strategy | — | level / flow / on-off | always |
| Rising main internal diameter | mm | number | if existing |
| Pump duty flow | l/s | number | if existing |
| Pump duty head | m | number | if existing |
| Pump shut-off head | m | number | if existing |
| Wet well plan area | m² | number | if existing |
Everything else — the main material, the instrument set, the itemised branch fittings, the overflow level, the surveyed wall roughness and pump efficiency — keeps the template's default. Four of those defaults are the instruments, expressed as four separate yes/no parameters (LT, LSHH, LSLL, FT) because the parameter system has no set type; none of them is asked on drop.
Editable setpoints (in the workspace)
Sixteen, grouped in the Simulate view by the loop whose node owns them:
| Setpoint | Unit |
|---|---|
| Stop level · PID setpoint · Duty start · Assist stop · Assist start · Last assist start | m |
| Minimum speed · No-flow check above | Hz |
| No-flow threshold per pump · Pass-forward flow setpoint | l/s |
| No-flow delay · Fail-to-start time · Auto reset after | s |
| Low-low float hardwired to drive safe-torque-off · FT fault inhibits no-flow check · Assist pumps stop one at a time | yes/no |
A setpoint that does not apply to your configuration is hidden rather than disabled — because the control node that owned it was not generated either. Choose direct-on-line over a variable-speed drive and the minimum-speed setpoint goes away with the node that read it.
The high-high and low-low float levels and the starts-per-hour allowance are deliberately not setpoints: the float levels are survey data, and the starts allowance comes from the rule set.
Control loops
Six families of generated graph, in scan order:
wet well → selector → each pump (one per installed pump) → floats (hardwired) → rising main → outstation
The float circuit runs even when the PLC is not energised — which is the whole reason it is generated as a graph rather than described in prose.
What the outputs mean
Published port values
| Port | What it publishes |
|---|---|
inlet | The flows the station is designed for — dry weather and design peak |
outlet | The maximum it passes forward, with the rising main's bore and the head at it |
signals | The size of its signal set |
For the reference configuration those read 4.0 / 12.0 l/s at the inlet, ≤ 12.0 l/s · DN100 · 10.5 m at the outlet and 37 signals.
Overview figures
Arrangement, control method, duty point of one pump, station capacity, rising main bore and material, motor rating, the number of design findings, and the number of control loops.
Live facts during a run
Titled Station: the clock, the wet-well level with the transmitter's reading beside it, in/out flows, the state of each pump, starts per hour, and the volume spilled.
Trend panels
Three: level (with the LT reading dashed over it, and reference lines at the overflow level, LSHH, duty start, stop and LSLL), flow (inflow and the flow meter), and pumps running.
The I/O schedule
Every point exists because a piece of the configuration exists: the level transmitter brings one analogue input; each pump brings five digital inputs, two digital outputs, one analogue output and two analogue inputs; the panel is sized from the totals plus the rule set's spare allowance. That is what makes the reference station exactly 37 points — 20 DI, 6 DO, 8 AI, 3 AO — and a fourth pump 47 without anyone editing a schedule.
The calculation chart
The pump and system curves, with the duty points marked:
| Series | Meaning |
|---|---|
| pump, 1 pump | the fitted pump curve at full speed, for the flow through one pump |
| pump, k pumps | the same curve read at q/k — k identical pumps on a common main share the total flow |
| system | static head plus the rising main's friction, over the total flow |
Faults you can inject
| Group | Cases |
|---|---|
| Level transmitter | fails · frozen · reads 0.5 m high |
| Floats | LSHH fails · LSHH stuck on · LSLL fails · LSLL stuck on |
| Pumps | duty trips · duty fails to start · duty blocked |
| Flow meter | fails · reads zero |
| Supply | power failure (2 h) |
A fault whose device is not fitted is not offered, so a station with no flow meter has two cases fewer. Fault names follow the station's area number — a station at area 2 names its duty-trip case against P-201.
Honest limits
- The run verdict and the design findings are shown on the workspace's Validation view; the single-fault suite is not run from it.
- The 1,680-combination configuration matrix and the single-fault suite are release gates run as automated tests, not as something you can start from the workspace.
- Nobody has recorded watching this unit run in a browser. The models are heavily tested; the on-screen behaviour of a run is not described here.