GAHE GHDS100E Energy Meter is equipped with RS485 Communication. Readings are retrieved by ESP8266 (Wemos Mini) running Modbus RTU library, then send the data directly to Thingspeak every 15 seconds.
Heat Pump Energy Monitor, based on PZEM 016. Data uplodaded with a ESP8266 (WEMOS D1 Mini) + IL9431 local display
Smart Energy Meter from Orno measured with a raspberry pi via modbus