WaterFleet reference stack

Bench test

Pending bench test — Validation status.

Fleet dashboard for water flow and pressure. Device type: water_meter.

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Telemetry contract

Key	Unit	Typical use
flow_rate	m³/h or L/min (document on device)	Instantaneous flow
total_volume_m3	m³	Integrator / totalizer register
pressure_bar	bar	Line or outlet pressure transducer

Align Modbus scale factors with manufacturer manuals (pulse constants for totalizer).

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Reference hardware (pending bench test)

Item	Detail
Flow	Electromagnetic flow meter with Modbus RTU (e.g. compact DN50 class meters — confirm register map in vendor manual)
Pressure	4–20 mA or Modbus pressure transmitter 0–10 bar class (map to pressure_bar)
Datasheet	Use vendor communication protocol appendix for register addresses and float/word order

Status: Pending bench test — two Modbus slaves on one RS485 bus (flow + pressure) or one integrated meter if it exposes all keys.

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Connectivity options

Profile	Edge	Link	Status
P1	4G DTU	Cloud Modbus master	Pending bench test
P2	ESP32 / edge GW	WiFi or Ethernet	Pending bench test
P3	Modbus TCP at pump room	Ethernet	Pending bench test

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Wiring — P1 / P2 (RS485 bus)

flowchart TB
  subgraph Field
    EM[Electromagnetic flow meter]
    PT[Pressure transmitter]
  end
  subgraph Edge
    EDGE[DTU or ESP32 master]
  end
  AC[Autoconnecto]
  EM -->|RS485| EDGE
  PT -->|RS485| EDGE
  EDGE <-->|MQTT| AC

Bus	Notes
RS485	Unique slave IDs; common baud (often 9600); termination at ends
Flow install	Straight pipe run per EM meter datasheet (upstream/downstream lengths)
Pressure	Tap location per hydraulic design; isolate for service

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Modbus mapping (conceptual)

Map from vendor manual — example pattern only:

Telemetry key	Typical source
flow_rate	Instantaneous flow register × scale
total_volume_m3	Totalizer (32-bit or float pair)
pressure_bar	Pressure register in bar or kPa × scale

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Autoconnecto checklist

• [ ] Create gateway + child devices linked with parentDeviceId (Sample On demos this topology)
• [ ] Child device type water_meter per site or per meter set (one device publishing all three keys)
• [ ] Units consistent with dashboard labels; telemetry on the child
• [ ] Optional hub health: publish gateway.heartbeat on the gateway token
• [ ] Gateway shows Active from hub heartbeat and/or any active child
• [ ] Spike-friendly ranges in alarms (burst flow vs leak)

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Related

• Connectivity profiles
• Reference stacks