# pumpingStation

> **Reflects code as of `530f84a` · regenerated `2026-05-11` via `npm run wiki:all`**
> If this banner is stale, the page may be out of date. Treat as informative, not authoritative.

## 1. What this node is

**pumpingStation** is an S88 Process Cell that owns a wet-well basin and orchestrates the pumps that drain it. It tracks measured and predicted volume, evaluates safety interlocks (dry-run, overfill), and dispatches a control strategy that hands a demand setpoint to one or more downstream machine groups or individual pumps. Stateful (control mode) and tick-driven (1 s integrator). See [`wiki/functional-description.md`](functional-description) for the full behaviour spec.

## 2. Position in the platform

```mermaid
flowchart LR
    meas_lvl[measurement<br/>type=level<br/>position=atequipment]:::ctrl
    meas_in[measurement<br/>type=flow<br/>position=upstream]:::ctrl
    ps[pumpingStation<br/>Process Cell]:::pc
    mgc[machineGroupControl<br/>Unit]:::unit
    pump[rotatingMachine<br/>Equipment]:::equip

    meas_lvl -->|level.measured.atequipment| ps
    meas_in -->|flow.measured.upstream| ps
    pump -->|child.register| mgc
    mgc -->|child.register| ps
    mgc -->|flow.predicted.downstream| ps
    ps -->|set.demand| mgc
    classDef pc fill:#0c99d9,color:#fff
    classDef unit fill:#50a8d9,color:#000
    classDef equip fill:#86bbdd,color:#000
    classDef ctrl fill:#a9daee,color:#000
```

S88 colours: Process Cell `#0c99d9`, Unit `#50a8d9`, Equipment `#86bbdd`, Control Module `#a9daee`. Source of truth: `.claude/rules/node-red-flow-layout.md §10.1`.

## 3. Capability matrix

| Capability | Status | Notes |
|---|---|---|
| Predicts basin volume from net flow | ✅ | Integrator seeded from `basin.minVol`; recomputes level each tick. |
| Accepts measured level / volume / pressure / flow | ✅ | Routed via `measurementRouter` on child registration. |
| Level-based control strategy | ✅ | Linear or log ramp between `startLevel` and `maxLevel`. |
| Flow-based control strategy | ✅ | PID against `flowSetpoint`. |
| Manual demand passthrough | ✅ | `set.demand` only honoured in `manual` mode. |
| Dry-run safety interlock | ✅ | Shuts downstream pumps when volume < `minVol` while draining. Blocks control. |
| Overfill safety interlock | ✅ | Shuts upstream equipment when volume > threshold while filling. Control keeps running. |
| No-data panic | ✅ | Shuts ALL machines and blocks control when no volume reading is available. |
| Cascaded sub-stations | ⚠️ | Accepted via `pumpingstation` softwareType but not exercised in production. |
| pressureBased / powerBased / hybrid modes | ❌ | Enumerated in schema but not dispatched — only `levelbased`, `flowbased`, `manual`. |

## 4. Code map

```mermaid
flowchart TB
    subgraph nodeRED["nodeClass.js — adapter (BaseNodeAdapter)"]
        nc["buildDomainConfig()<br/>static DomainClass, commands<br/>static tickInterval = 1000 ms"]
    end
    subgraph domain["specificClass.js — orchestrator (BaseDomain)"]
        sc["PumpingStation.configure()<br/>declares ChildRouter rules<br/>tick() → flowAggregator → safety → control"]
    end
    subgraph concerns["src/ concern modules"]
        basin["basin/<br/>BasinGeometry · thresholdValidator"]
        measurement["measurement/<br/>flowAggregator · measurementRouter · calibration"]
        control["control/<br/>levelBased · flowBased · manual · dispatch"]
        safety["safety/<br/>SafetyController"]
        commands["commands/<br/>topic registry · handlers"]
    end
    nc --> sc
    sc --> basin
    sc --> measurement
    sc --> control
    sc --> safety
    nc --> commands
```

| Module | Owns | Read first if you're changing… |
|---|---|---|
| `basin/` | Geometry, volume↔level conversion, threshold ordering | Capacity, level↔volume math, fill %. |
| `measurement/` | Net-flow aggregation, predicted-volume integrator, calibration | Predicted volume / time-to-full. |
| `control/` | Strategy dispatch (`levelbased`, `flowbased`, `manual`) | Demand calculation, mode behaviour. |
| `safety/` | Dry-run + overfill rules, pump-shutdown side-effects | Safety envelope, alarm reactions. |
| `commands/` | Input-topic registry and handlers | New input topics, payload validation. |

## 5. Topic contract

> **Auto-generated** from `src/commands/index.js`. Do NOT hand-edit between the markers. Re-run `npm run wiki:contract`.

<!-- BEGIN AUTOGEN: topic-contract -->

| Canonical topic | Aliases | Payload | Unit | Effect |
|---|---|---|---|---|
| `set.mode` | `changemode` | `string` | — | Switch the station between auto / manual control modes. |
| `child.register` | `registerChild` | `string` | — | Register a child node (machine group, measurement, …) with this station. |
| `cmd.calibrate.volume` | `calibratePredictedVolume` | `any` | `volume` (default `m3`) | Calibrate the predicted-volume integrator to a known basin volume. |
| `cmd.calibrate.level` | `calibratePredictedLevel` | `any` | `length` (default `m`) | Calibrate the predicted-volume integrator to a known basin level. |
| `set.inflow` | `q_in` | `any` | `volumeFlowRate` (default `m3/h`) | Push a measured inflow value into the basin balance. |
| `set.outflow` | `q_out` | `any` | `volumeFlowRate` (default `m3/h`) | Push a measured outflow value into the basin balance. |
| `set.demand` | `Qd` | `any` | `volumeFlowRate` (default `m3/h`) | Operator outflow demand setpoint for the station. |

<!-- END AUTOGEN: topic-contract -->

## 6. Child registration

Mirrors the `ChildRouter` declarations in `specificClass.js → configure()`.

```mermaid
flowchart LR
    subgraph kids["accepted children (softwareType)"]
        m["measurement"]:::ctrl
        mach["machine<br/>(rotatingMachine)"]:::equip
        mgc["machinegroup<br/>(machineGroupControl)"]:::unit
        sub["pumpingstation<br/>(sub-station)"]:::pc
    end
    m -->|"&lt;type&gt;.measured.&lt;position&gt;"| route1[_subscribeMeasurement<br/>→ measurementRouter]
    mach -->|flow.predicted.out| route2[_subscribePredictedFlow<br/>+ flowAggregator]
    mgc -->|flow.predicted.out| route2
    sub -->|flow.predicted.out| route2
    route1 --> tick[tick / integrator]
    route2 --> tick
    classDef ctrl fill:#a9daee,color:#000
    classDef equip fill:#86bbdd,color:#000
    classDef unit fill:#50a8d9,color:#000
    classDef pc fill:#0c99d9,color:#fff
```

| softwareType | onRegister side-effect | Subscribed events |
|---|---|---|
| `measurement` | `_subscribeMeasurement(child)` — writes to MeasurementContainer by type + position. | `<type>.measured.<position>` for any type (level, flow, pressure, …). |
| `machine` | Added to `this.machines`. **Skipped when a `machinegroup` is present** — avoids double-counting predicted flow. | `flow.predicted.<in\|out>` per `positionVsParent`. |
| `machinegroup` | Added to `this.machineGroups`. | `flow.predicted.<in\|out>`. |
| `pumpingstation` | Added to `this.stations`. | `flow.predicted.<in\|out>`. |

## 7. Lifecycle — what one tick does

```mermaid
sequenceDiagram
    participant child as measurement / pump child
    participant ps as pumpingStation
    participant fa as flowAggregator
    participant sf as safetyController
    participant ctl as control strategy
    participant out as Port-0 output

    child->>ps: data event (level.measured.atequipment / flow.predicted.out)
    ps->>ps: ChildRouter dispatches to _subscribeMeasurement / _subscribePredictedFlow
    Note over ps: every 1000 ms (static tickInterval = 1000)
    ps->>fa: tick() — net flow · ETA · predicted volume integrator
    ps->>sf: evaluate({direction, secondsRemaining})
    alt no-volume-data panic
        sf-->>ps: blocked=true, reason='no-volume-data'
        sf-->>ps: ALL machines shut down
    else dry-run (vol < minVol AND draining)
        sf-->>ps: blocked=true, reason='dry-run'
        sf-->>ps: downstream machines + machineGroups shut down
    else overfill (vol > threshold AND filling)
        sf-->>ps: blocked=false, reason='overfill'
        sf-->>ps: upstream machines + child stations shut down
        ps->>ctl: dispatch(mode, ctx, controlState)
        ctl-->>ps: percControl updated — pumps keep draining
    else safety clear
        ps->>ctl: dispatch(mode, ctx, controlState)
        ctl-->>ps: percControl updated
    end
    ps->>ps: notifyOutputChanged()
    ps->>out: msg{topic, payload (delta-compressed)}
```

For control-strategy details see [`wiki/modes/`](modes/README).

## 8. Data model — `getOutput()`

What lands on Port 0. Built in `getOutput()`, then delta-compressed by `outputUtils.formatMsg`.

<!-- BEGIN AUTOGEN: data-model -->

| Key | Type | Unit | Sample |
|---|---|---|---|
| `direction` | string | — | `"steady"` |
| `dryRunLevel` | number | — | `0.20400000000000001` |
| `dryRunSafetyVol` | number | — | `0.20400000000000001` |
| `flowSource` | null | — | `null` |
| `heightBasin` | number | m | `1` |
| `highVolumeSafetyLevel` | number | — | `2.45` |
| `highVolumeSafetyVol` | number | — | `2.45` |
| `inflowLevel` | number | m | `2` |
| `inletPipeDiameter` | number | — | `0.4` |
| `maxVol` | number | m3 | `1` |
| `maxVolAtOverflow` | number | m3 | `2.5` |
| `minHeightBasedOn` | string | — | `"outlet"` |
| `minVol` | number | m3 | `0.2` |
| `minVolAtInflow` | number | m3 | `2` |
| `minVolAtOutflow` | number | m3 | `0.2` |
| `outflowLevel` | number | m | `0.2` |
| `outletPipeDiameter` | number | — | `0.4` |
| `overflowLevel` | number | m | `2.5` |
| `percControl` | number | % | `0` |
| `predictedOverflowRate` | number | — | `0` |
| `predictedOverflowVolume` | number | — | `0` |
| `predictedUnderflowVolume` | number | — | `0` |
| `surfaceArea` | number | m2 | `1` |
| `timeleft` | null | s | `null` |
| `volEmptyBasin` | number | m3 | `1` |
| `volume.predicted.atequipment.wikigen-pumpingstation-id` | number | m3 | `0.2` |

<!-- END AUTOGEN: data-model -->

The `<nodeId>` segment of the MeasurementContainer key is the Node-RED node id assigned at deploy time; auto-gen substitutes a placeholder stub.

## 9. Configuration — editor form ↔ config keys

```mermaid
flowchart TB
    subgraph editor["Node-RED editor form"]
        f1[Basin: volume / height]
        f2[Levels: inflow / outflow / overflow]
        f3[Control mode]
        f4[Level-based setpoints: startLevel / stopLevel / minLevel / maxLevel]
        f5[Safety: dry-run % / high-volume %]
    end
    subgraph config["Domain config slice"]
        c1[basin.volume<br/>basin.height]
        c2[basin.inflowLevel<br/>basin.outflowLevel<br/>basin.overflowLevel]
        c3[control.mode]
        c4[control.levelbased.startLevel<br/>control.levelbased.stopLevel<br/>control.levelbased.minLevel<br/>control.levelbased.maxLevel]
        c5[safety.dryRunThresholdPercent<br/>safety.highVolumeSafetyThresholdPercent]
    end
    f1 --> c1
    f2 --> c2
    f3 --> c3
    f4 --> c4
    f5 --> c5
```

| Form field | Config key | Default | Range | Where used |
|---|---|---|---|---|
| `basinVolume` | `basin.volume` | `1` | > 0 (m³) | `BasinGeometry` |
| `basinHeight` | `basin.height` | `1` | > 0 (m) | `BasinGeometry` |
| `inflowLevel` | `basin.inflowLevel` | `0.8` | ≥ 0 (m) | threshold validator, control ramp foot |
| `outflowLevel` | `basin.outflowLevel` | `0.2` | ≥ 0 (m) | dead-volume floor |
| `overflowLevel` | `basin.overflowLevel` | `0.9` | > 0 (m) | overfill safety ceiling |
| `controlMode` | `control.mode` | `levelbased` | enum | `control/dispatch` |
| `levelCurveType` | `control.levelbased.curveType` | `linear` | `linear` \| `log` | `levelBased.run` |
| `logCurveFactor` | `control.levelbased.logCurveFactor` | `9` | > 0 | log-curve steepness |
| `enableShiftedRamp` | `control.levelbased.enableShiftedRamp` | `false` | bool | hysteresis ramp |
| `startLevel` | `control.levelbased.startLevel` | `null` | ≥ 0 (m) | ramp zero-point |
| `stopLevel` | `control.levelbased.stopLevel` | `null` | ≥ 0 (m) | Schmitt-trigger off threshold |
| `minLevel` | `control.levelbased.minLevel` | `null` | ≥ 0 (m) | `levelBased.run` |
| `maxLevel` | `control.levelbased.maxLevel` | `null` | ≤ overflowLevel (m) | ramp 100 % point |
| `flowSetpoint` | `control.flowbased.setpoint` | `null` | ≥ 0 (m³/h) | flow-PID target |
| `enableDryRunProtection` | `safety.enableDryRunProtection` | `true` | bool | `SafetyController._dryRunRule` |
| `dryRunThresholdPercent` | `safety.dryRunThresholdPercent` | `2` | 0–100 % | dry-run trip volume |
| `enableHighVolumeSafety` | `safety.enableHighVolumeSafety` | `true` | bool | `SafetyController._overfillRule` |
| `highVolumeSafetyThresholdPercent` | `safety.highVolumeSafetyThresholdPercent` | `98` | 0–100 % | overfill trip volume |
| `timeleftToFullOrEmptyThresholdSeconds` | `safety.timeleftToFullOrEmptyThresholdSeconds` | `0` | ≥ 0 (s) | ETA-based pre-trip guard |

> `enableOverfillProtection` and `overfillThresholdPercent` are **deprecated aliases** still accepted by `SafetyController` for back-compat. Use `enableHighVolumeSafety` and `highVolumeSafetyThresholdPercent` in new flows. See `OPEN_QUESTIONS.md` (B1.2 resolved).

## 10. State chart

pumpingStation has two orthogonal state vectors: **control mode** (operator-driven, persistent) and **safety state** (data-driven, evaluated every tick). The e-stop path is the no-volume-data panic that shuts all machines independently.

```mermaid
stateDiagram-v2
    state ControlMode {
        [*] --> levelbased
        levelbased --> flowbased : set.mode
        flowbased --> manual : set.mode
        manual --> levelbased : set.mode
        manual --> none : set.mode
        levelbased --> none : set.mode
        none --> levelbased : set.mode
    }

    state SafetyState {
        [*] --> nominal
        nominal --> dryRun : vol < minVol AND draining
        nominal --> overfill : vol > highVolThreshold AND filling
        nominal --> panic : no volume reading
        dryRun --> nominal : vol ≥ minVol
        overfill --> nominal : vol ≤ highVolThreshold
        panic --> nominal : volume reading restored
    }
```

| Safety state | `blocked` | Control dispatch | Side-effects |
|---|---|---|---|
| `nominal` | false | runs normally | — |
| `dryRun` | **true** | **skipped** | downstream machines + machineGroups shut down |
| `overfill` | false | runs (pumps must drain) | upstream machines + child stations shut down |
| `panic` | **true** | **skipped** | **ALL** machines shut down |

`dryRun` is triggered when `direction='draining'` AND vol < `minVol × (1 + dryRunThresholdPercent/100)`.
`overfill` is triggered when `direction='filling'` AND vol > `maxVolAtOverflow × (highVolumeSafetyThresholdPercent/100)`.

## 11. Examples

All three tiers are written and runnable. Import any file via the Node-RED editor or the Admin API.

| Tier | File | What it shows | Status |
|---|---|---|---|
| Basic | `examples/01-Basic.json` | Single pumpingStation driven by inject nodes — no parent, no dashboard. Try `set.inflow`, `set.mode`, `cmd.calibrate.volume`. | ✅ |
| Integration | `examples/02-Integration.json` | pumpingStation + `machineGroupControl` + 2 `rotatingMachine` pumps + level `measurement`. Demonstrates Phase-2 parent/child handshake and `levelbased` control driving real pumps. | ✅ |
| Dashboard | `examples/03-Dashboard.json` | Tier 2 plumbing + FlowFuse Dashboard 2.0 page — 3 charts (flow / level / volume %), mode dropdown, demand slider. | ✅ |
| Headless | `examples/standalone-demo.js` | Node.js-only simulator, no Node-RED required. | ✅ |

See `examples/README.md` for layout conventions (link channels, lane positions, group boxes).

## 12. Debug recipes

| Symptom | First thing to check | Where to look |
|---|---|---|
| Status badge stuck on `❔ 0.0%` | No volume/level measurement registered yet. Watch Port 2. | Editor debug tap on Port 2 + `_subscribeMeasurement` log line. |
| `direction` always `steady` | Net flow inside `general.flowThreshold` dead-band (default 0.0001 m³/s ≈ 0.36 m³/h). | `flowAggregator.deriveDirection`. |
| `set.demand` ignored | Mode isn't `manual`. Confirm with `set.mode=manual` first. | `handlers.setDemand` debug log. |
| Predicted volume drifts off measured | Integrator needs a calibration anchor. Fire `cmd.calibrate.volume` with a known basin volume. | `measurement/calibration.js`. |
| Pumps don't stop on dry-run | `safety.enableDryRunProtection` must be `true` AND `direction` must be `'draining'`. | `SafetyController._dryRunRule`. |
| Threshold-ordering warnings on startup | `validateThresholdOrdering` detected violations (e.g. `inflowLevel > overflowLevel`). | `basin/thresholdValidator.js`. |
| All machines shut down immediately | No volume reading reached the node — panic path in SafetyController. Check child registration sequence. | `SafetyController.evaluate` line 59. |

> Never ship `enableLog: 'debug'` in a demo — fills the container log within seconds and obscures real errors. Use only for live debugging.

## 13. When you would NOT use this node

- Use `rotatingMachine` directly for a single pump with no basin model. pumpingStation adds overhead that pays off only when you need predicted volume, time-to-full, or multi-pump orchestration.
- Don't use pumpingStation to schedule a fixed pump rota. Its control modes are reactive (level / flow / manual demand), not calendar-driven. Use an external scheduler and wire it in via `set.demand`.
- Skip pumpingStation if you only need flow or pressure measurements with no wet-well state. A bare `machineGroupControl` is lighter when the basin is modelled elsewhere or not at all.

## 14. Known limitations / current issues

| # | Issue | Tracked in |
|---|---|---|
| 1 | Cascaded `pumpingstation` children accepted but semantics of nested stations are not test-covered in production scenarios. | TBD — exercise in Docker E2E before promoting. |
| 2 | `pressureBased`, `percentageBased`, `powerBased`, and `hybrid` are listed in the config enum but not dispatched — only `levelbased`, `flowbased`, `manual` are implemented. | `control/index.js` |
| 3 | Predicted-volume integrator drifts over long horizons without a measured-level calibration source. `cmd.calibrate.volume` is operator-triggered, not automatic. | Operator procedure; auto-calibration from level sensor is future work. |
| 4 | `enableOverfillProtection` / `overfillThresholdPercent` deprecated aliases still accepted by `SafetyController` (back-compat). Remove after one release cycle. | B1.2 resolved in `OPEN_QUESTIONS.md`. |