sdm630-report

Tools for monitoring an SDM630 3 phase meter and reporting output to PVoutput

Main C code is from Mario Stuetz in thread 123solar Eastron SDM630 DC

Current Features

• Reads current values over MODBUS from a Eastron SDM630 digital meter and exports to an ini file
• Uploads data to PVOutput for analyses and graphing
• Can download weather data to include in upload

Requirements

• Eastron SDM630 DC installed in main switchboard
• USB to RS485 adaptor.
  • I used a USB to RS485 TTL Serial Converter Adapter FTDI interface FT232RL 75176 Module S
• Or a TCP-RS485 e.g. Q14870 USR-TCP232-304 or Q00194 USR-TCP232-24
• sdm630-usb requires ModBus Libraries
• Scripts are written in Python3
• Python3 script for PVOutput requires requests

Installation

1. If installing on Raspberry Pi, I suggest using a ram disk for storage to prevent wear on SD card. The downside to a ram disk is you will lose data if power is lost or Pi is rebooted before upload occurs.

   1. Create a tmp directory mount point for RAM disk

      sudo mkdir /var/tmp

   2. Add the following to bottom of /etc/fstab

      tmpfs /var/tmp tmpfs nodev,nosuid,size=1M 0 0
      

   3. Mount the RAM disk to create it

      sudo mount /var/tmp

2. Install libraries for modbus

   sudo aptitude install libmodbus-dev libmodbus5

   Compile with

   gcc sdm630-usb.c -o sdm630 `pkg-config --cflags --libs libmodbus`

3. Copy files

   sudo mkdir /opt/sdm630
   sudo cp config/sdm630.conf /etc/
   sudo cp import/* /opt/sdm630/
   sudo cp output/* /opt/sdm630/

4. Edit /etc/sdm630.conf config file

   • Add your PVOutput API Key and System ID.
   • If you are not a PVOutput donor make sure you set PVextend to false.
   • Enter Weather Underground API and Station ID.

Crontab entries

Edit cron files using crontab -e

*/5 *   *   *   *    /opt/sdm630/sdm630-poll.sh
3-59/5 *   *   *   *    /opt/sdm630/pvoutput.py
2-59/5 *   *   *   *    /opt/sdm630/downloadWeather.sh

TODO

• SNMP extension to allow data collection by Cacti or other SNMP tools