Moving from the ESP8266 world I’ve been diving lately I still love the simplicity of battery powered Moteino nodes. You might know I’m migrating my XBee-based sensor network at home to an RFM69 one. So long I have changed my door monitor and my weather station. They are sensing and reporting to my RFM69GW, an ESP8266 bridge board using a custom firmware.
Time to go for the power monitor. A long time ago (actually 2 years but it really feels like a century ago) I was living in a big city and we had one of those fancy “smart meters” with a LED pulsing 4000 times every kWh. Back then I used an Arduino micro to count the LED pulses and report the power every minute through an XBee link.
But now I live in a small town and my house electrical system is somewhat “old”. My power meter comes from somewhen in the 60s (maybe not so old). So a non-invasive current sensor makes a bit more sense (ehem).
Some days ago I posted about the RFM69 to MQTT gateway based on the ESP8266 I am working on. Over these days I’ve been fine tuning the gateway at the same time I was migrating one of my home sensors to Moteino: the Door Monitor. The previous version was based on an XBee radio and has been on duty for almost 3 years and a half. Real life battery time has been around 3 months for a CR2032 coin cell, which is not bad at all, but still…
Aside from using a Moteino and a RFM69 868MHz radio instead of the XBee, I have reduced the components list by moving hardware logic to software logic. This means using sleeping capabilities of both the ATMega328 and the RFM69 and coding in a clever way to reduce awake time.