ModbusLogMQTT

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 and reading values from a WEBIQ131D / SDM120. By changing the meters.yml file and making a corresponding [model].yml file it should be possible to use other models.

Requirements

Hardware

• Raspberry Pi 3
• Linksprite RS485 Shield V3 for RPi
• 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

• Download Raspbian Stretch Lite and Flash on SD-card, e.g. by using Etcher
• Mount the RS485 shield on the Raspberry Pi’s GPIO header and connect the RS485 cables.

• Power up Rasberry Pi and setup password (passwd) and SSH, localization, network etc. using

  $ sudo raspi-config
  

• With raspi-config open, go to 5 Interfacing Options -> P6 Serial and Disable serial login shell and Enable serial port hardware (i.e. NO and then YES)

• To be able to use the UART you need to disable the built in Bluetooth since it shares the UART. To do so, add the following lines to /boot/config.txt source

  # Disable built in Bluetooth
  dtoverlay=pi3-miniuart-bt
  

• To disable the serial console, you need to edit the /boot/cmdline.txt file to look like the following row. source

  dwc_otg.lpm_enable=0 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait
  

• Install Python Package Manager PIP if not already installed (not installed on Raspbian Lite):

  $ sudo apt-get install python-pip
  

• Install Git if not already installed (not installed on Raspbian Lite):

  $ sudo apt-get install git
  

Installation

Install InfluxDB

source

Step-by-step instructions

• Add the InfluxData repository

  $ curl -sL https://repos.influxdata.com/influxdb.key | sudo apt-key add -
  $ source /etc/os-release
  $ test $VERSION_ID = "9" && echo "deb https://repos.influxdata.com/debian stretch stable" | sudo tee /etc/apt/sources.list.d/influxdb.list
  

• Download and install

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

• Start the influxdb service

  $ sudo service influxdb start
  $ sudo service influxdb restart
  

• Create the database

  $ sudo influx
  CREATE DATABASE db_meters
  exit

  

Install Grafana

source

Step-by-step instructions

• Add APT Repository

  $ echo "deb https://dl.bintray.com/fg2it/deb-rpi-1b jessie main" | sudo tee -a /etc/apt/sources.list.d/grafana.list
  

• Add Bintray key

  $ curl https://bintray.com/user/downloadSubjectPublicKey?username=bintray | sudo apt-key add -
  

• 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
  

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

Install Energy Meter Logger:

• Download and install from Github

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

• Run setup script

  $ 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
  

• 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