Energy Meter Logger

Log your Energy Meter data on a Raspberry Pi and plot graphs of your energy consumption. Its been verified to work with a Raspberry Pi with a Linksprite RS485 shield or with generic cheap USB convertor and reading values from WEBIQ131D / SDM120 and WEBIQ343L / SDM630. By changing the meters.yml file and making a corresponding [model].yml file it should be possible to use other modbus enabled models.

Requirements

Hardware

• Raspberry Pi 3
• Linksprite RS485 Shield V3 for RPi (discontinued and not suitable fro Pi4b and above)
• OR
• cheap generic USB convertor (like this one https://a.aliexpress.com/_ufjPgJ)
• Modbus based Energy Meter, e.g WEBIQ 131D / Eastron SDM120 or WEBIQ 343L / Eastron SMD630

Software

• Rasbian
• Python 2.7 and PIP
• Minimalmodbus
• InfluxDB
• Grafana

Prerequisite

This project has been documented at Hackster. Please follow the instructions there for more detailed information.

Installation

Install InfluxDB*

Step-by-step instructions

• Add the InfluxData repository (change the debian release accoring to one you use, below is for buster)

  $ curl -sL https://repos.influxdata.com/influxdb.key | sudo apt-key add -
  $ source /etc/os-release
  $ sudo test $VERSION_ID = "10" && echo "deb https://repos.influxdata.com/debian buster stable" | sudo tee /etc/apt/sources.list.d/influxdb.list

• Download and install

  $ sudo apt-get update && sudo apt-get install influxdb

• Unmask the influxdb service

  $ sudo systemctl unmask influxdb.service

• Start the influxdb service

  $ sudo systemctl start influxdb

• Create the database

  $ influx
  CREATE DATABASE db_meters
  exit

*source

Install Grafana*

Step-by-step instructions

• Add APT Repository and key

  sudo apt-get install -y apt-transport-https
  sudo apt-get install -y software-properties-common wget
  wget -q -O - https://packages.grafana.com/gpg.key | sudo apt-key add -

• Add Repository to package manager for stable channel

  echo "deb https://packages.grafana.com/oss/deb stable main" | sudo tee -a /etc/apt/sources.list.d/grafana.list

• Now install

  $ sudo apt-get update && sudo apt-get install grafana

• Start the service using systemd:

  $ sudo systemctl daemon-reload
  $ sudo systemctl start grafana-server
  $ systemctl status grafana-server

• Enable the systemd service so that Grafana starts at boot.

  $ sudo systemctl enable grafana-server.service
  $ sudo service grafana-server start
  $ sudo service grafana-server status
  $ sudo update-rc.d grafana-server defaults

• Go to http://localhost:3000 and login using admin / admin (remember to change password) *source

Install Energy Meter Logger:

• Download and install from Github

  $ git clone https://github.com/samuelphy/energy-meter-logger

• Run setup script (must be executed as root (sudo) if the application needs to be started from rc.local, see below)

  $ cd energy-meter-logger
  $ sudo python setup.py install

• Make script file executable

  $ chmod 777 read_energy_meter.py

• Edit meters.yml to match your configuration
• Test the configuration by running:

  ./read_energy_meter.py
  ./read_energy_meter.py --help # Shows you all available parameters

• To run the python script at system startup. Add to following lines to the end of /etc/rc.local but before exit:

  # Start Energy Meter Logger
  /home/pi/energy-meter-logger/read_energy_meter.py --interval 60 > /var/log/energy_meter.log &

  Log with potential errors are found in /var/log/energy_meter.log