This design is almost identical to the Smart Energy Groups SEGMeter (for which kits can be purchased, from Sam @ Smart Energy Groups), however, I have started making some improvements. (When I find where I put the original CAD/CAM files that actually correspond to the SEGMeter boards that exist already, I will upload those too.)
- The schematic is drawn significantly more cleanly and tidy
- Integrated AVR on the board (that is, not an Arduino shield)
- Surface-mount components used, making the board smaller and more compact and (arguably) easier to assemble
- Programming of the AVR through the Arduino IDE is done using an external FTDI adapter, just like the Arduino Pro.
- A header is provided to connect a phototransistor, which can be stuck onto the front of a modern electricity meter to read the frequency of the flashing LED.
- An open-collector transistor output (connected to 12 V) is provided on the board instead of a low-current reed relay. This can be connected to the coil of a power relay to switch 240 VAC.
Things to do:
- Design and test improvments to the analog input filter/coupling circuits
- Fix the silkscreen layers on the PCB so they're neatly arranged and tidy, in the appropriate places, and not overlapping or over the pads.
- Run ERC and DRC
- Generate Gerber files