# 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](http://linksprite.com/wiki/index.php5?title=RS485/GPIO_Shield_for_Raspberry_Pi_V3.0)
* Modbus based Energy Meter, e.g WEBIQ 131D / Eastron SDM120 or WEBIQ 343L / Eastron SMD630

#### Software

* Rasbian
* Python 2.7 and PIP
* [Minimalmodbus](https://minimalmodbus.readthedocs.io/en/master/)
* [InfluxDB](https://docs.influxdata.com/influxdb/v1.3/)
* [Grafana](http://docs.grafana.org/)

### Prerequisite

* [Download Raspbian Stretch Lite](https://www.raspberrypi.org/downloads/raspbian/) 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
    ```sh
    $ 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](http://www.briandorey.com/post/Raspberry-Pi-3-UART-Boot-Overlay-Part-Two)
    ```sh
    # 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](http://www.briandorey.com/post/Raspberry-Pi-3-UART-Boot-Overlay-Part-Two)
    ```sh
    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):
    ```sh
    $ sudo apt-get install python-pip
    ```
* Install Git if not already installed (not installed on Raspbian Lite):
    ```sh
    $ sudo apt-get install git
    ```    

### Installation
#### Install InfluxDB
[source](https://docs.influxdata.com/influxdb/v1.3/introduction/installation/)

##### Step-by-step instructions
* Add the InfluxData repository
    ```sh
    $ 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
    ```sh
    $ sudo apt-get update && sudo apt-get install influxdb
    ```
* Start the influxdb service
    ```sh
    $ sudo service influxdb start
    ```
* Create the database
    ```sh
    $ influx
    CREATE DATABASE db_meters
    exit

    ```

#### Install Grafana
[source](http://docs.grafana.org/installation/debian/)

##### Step-by-step instructions
* Add APT Repository
    ```sh
    $ 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
    ```sh
    $ curl https://bintray.com/user/downloadSubjectPublicKey?username=bintray | sudo apt-key add -
    ```
* Now install
    ```sh
    $ sudo apt-get update && sudo apt-get install grafana

    ```
* Start the service using systemd:
    ```sh
    $ sudo systemctl daemon-reload
    $ sudo systemctl start grafana-server
    $ systemctl status grafana-server
    ```
* Enable the systemd service so that Grafana starts at boot.
    ```sh
    $ 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
    ```sh
    $ 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)
    ```sh
    $ cd energy-meter-logger
    $ sudo python setup.py install
    ```    
* Make script file executable
    ```sh
    $ chmod 777 read_energy_meter.py
    ```
* Edit meters.yml to match your configuration
* Test the configuration by running:
    ```sh
    ./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:
    ```sh
    # 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