A smart meter connected to a pi-like device, to notify when the main water pipe is broken, and prevent major leaks that can cost money.
Some info about the project here: https://forums.balena.io/t/build-log-detecting-if-the-main-water-pipe-breaks
Instead of hardocding the SmartMeter register addresses, the project implements a generic datamodel parser to allow different configurations and/or devices.
The project is meant to run on balena, but the main script works in any PC
Using this HAT to add RS485 to the balenaFin.
For the initial project I've used this smart meter that includes a modbus slave with many parameters. As per my interest, I've only included in the datamodel the ones I'm going to process. The following is an extract from the manufacturer's doc:
| Register address | Register number | Register Name | Data format | Description |
|---|---|---|---|---|
| 0001-0002 | 2 | Instant flow rate | IEEE754 | Unit: m3/h |
| 0137-0138 | 2 | Daily accumulated flow rate | LONG | 9 Digits |
| 0141-0142 | 2 | Monthly accumulated flow rate | LONG | |
| 0361-0362 | 2 | Always display 361.00 | IEEE754 | For test |
There are basically different existing services and balenaBlocks from the meter to the algorithm that detects the Leak:
- tcpmodbus2mqtt: By defining a parameter's datamodel, it reads the MODBUS slave and publishes value to an MQTT server
- mqtt: A mosquito server
- connector: Intelligently connect data sources with data sinks.
- influxdb: A database to store read data
- dashboard: A customizable data visualization tool with automatically generated dashboards.
And finally, the algorith that detects the Leaks, basically detecting when there's water running for too long: the smartmeterprocessor service.
You can try this setup in your PC running a node-red server with the right modules.
- Load
utils/flows.jsonfile in node-red to run the modbus server simulator. It will act as a smart meter, or any other modbus slave. - Configure the server with the IP address of your PC
- Run
utils/randomModbusInjector.pyto populate the slave sim with some random data. Beware that the script has the parameters hardcoded, so if you change thedatamodel.jsonfile you will have to adapt this script. Also, change the IP address to match with the above
Note: The MQTT broker is not needed for the simulator. You will receive a warning, but the script will run
Some inspiration on:
- alanb128 for the algorithm
- balenaLabs and all balena team for the great product and support