# LRPR — Filter Pressure Sensor (LRPR-0D6800)

**Module ID**: `6a17218be0b88ea3e925524f`  
**Serial**: `1D00010D68000001`  
**MAC**: `C8:B9:61:0D:68:00`  
**UUID**: `1D0058B9610D680000000001000D6800`  
**Firmware**: 6.3.0 | **Hardware**: A | **Manufacturer**: `1D`  
**Type**: `lr-pr`  
**Role**: Measures filter pressure — indicates filter cleanliness / pump running state

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## Input

| Input ID | Type | Unit | Interval |
|---|---|---|---|
| `6a17218be0b88ea3e9255251` | 8 (pressure) | bar (unit code 6) | 1 min |

Raw-to-bar expression: `(1.5 × raw − 500) / 1000`

### Latest readings (2026-06-04)

```
16:01  0.091 bar  ← pump stopped / off
16:00  0.715 bar
15:59  0.741 bar
15:58  0.730 bar
18:41  0.081 bar  ← pump off
```

Normal operating pressure ~0.70–0.75 bar. Drop to ~0.08 bar signals pump has stopped.  
This sensor can be used to detect filtration start/stop and detect dirty filter (rising pressure).

---

## Remote state

- Battery: **94%**
- Last radio contact: 2026-06-04T20:05:14Z
- Relay: `60ca4276ad69dac1558f7c61` (LRMB10)
- No programs, no outputs — pure sensor

---

## Pressure Alert Configuration

From `poolPressureAlertsVariables` in the input object (retrieved via mobile API):

| Parameter | Value | Meaning |
|---|---|---|
| `staticPressure` | 0.919 bar | Baseline pressure at pump start |
| `nominalPressure` | 1.7275 bar | Expected operating pressure |
| `maximalPressure` | 1.0615 bar | Upper alert threshold |
| `atmosphericPressure` | 1.015 bar | Calibration reference |
| `filterCloggedMargin` | 0.5 bar | Rise above static = filter clogged alert |
| `filterPreCloggedMargin` | 0.3 bar | Rise above static = pre-clog warning |
| `activeFilterCloggedAlert` | true | Filter clog alert enabled |
| `activeWaterLevelLowAlert` | true | Low water level alert enabled |
| `activeSuctionValveClosedAlert` | true | Suction valve closed alert enabled |
| `waterLevelLowCount` | 6 | Ticks below threshold before alert |

## Notes

- `secondaryBatteryVoltage: 80` — secondary power source present
- Unit code 6 = bar; type 8 = pressure sensor
- Backwash reminder alerts fire every ~15 days (shared with pool notebook)