Last December Itead Studio updated their Home Automation product line with a new and different product. The main difference is that it doesn’t have a relay and it’s mainly sensors and no actuator (if we don’t define a notifying LED as an actuator). The Sonoff SC is a sensor station that packs a DHT11 temperature and humidity sensor, a GM55 LDR, an electret microphone with an amplifier circuit and a Sharp GP2Y1010AU0F dust sensor in a fancy case that looks like it was originally meant for a speaker.
The device is packs an ESP8266 as expected and is compatible with the eWeLink app. But, such a collection of sensors, with 3 of them having analog interfaces, cannot be run from the single-ADC ESP8266 so Itead has thrown in a good old ATMega328P to drive the sensors and report the Espressif with the data.
November was a busy month and the Sonoff Dual that IteadStudio kindly sent me to review was bored in a box waiting for some free time. But it was just fair that another board that has been waiting in the boards-to-review box for longer had it’s chance to have some fresh air too. So here we have the Itead Studio Sonoff Dual and the Electrodragon ESP Relay Board face to face.
My daughters love to talk to (or with) my Amazon Dot [Amazon US] in their funny English: “Alexa, hello!”, “Alexa, li-on!” (actually “light on”). It’s so easy to use it to switch on/off things at home using the fauxmo python script by Maker Musings. In his post about Amazon Echo and Home Automation more than a year ago he explains how he reverse-engineered the protocol of the WeMo switches that Alexa (Amazon Echo [Amazon US] or Amazon Dot [Amazon US]) supports.
I also have a server running the fauxmo script with an MQTT handler to control some of the Sonoffs I have at home, but this morning I woke up thinking: why should I use an external script to control my devices if I can code it in the firmware?
Some months ago I wrote about a hack I did to one of my Sonoff devices to be able to use a simple current sensor to monitor my washer machine process and alert me whenever my laundry was done.
A few weeks ago Itead Studio released two new models for their Sonoff line, the POW and the DUAL. And the POW is Itead’s answer to my hack. I’m not saying they copied me, just that the Sonoff POW makes my hack utterly unnecessary. Do you want to remotely monitor your devices energy consumption? Buy a POW.
The HLW8012 is single phase energy monitor chip by the chinese manufacturer HLW Technology. It features RMS current, RMS voltage sampling and RMS active power with an internal clock and a PWM interface in a SOP-8 package. You can buy it at Aliexpress for less than a euro a piece and the necessary components are fairly easy to source and quite cheap.
All in all it looks like a great IC to include power monitoring in your projects. I guess that is why Itead Studio chose it for the Sonoff POW, one of their newest home automation products. And of course I have a POW here in my desk and I’ve been playing with it this weekend. The goal is to support it in my Espurna firmware but first I wanted to know more about the HLW8012. I’ll write about the Sonoff POW in a different post later this week.