Have you ever forgotten your wet clothing inside the washer for a whole day? I have. Even for two days. They smell. You have to wash them again and you know you might end up forgetting about them again!
Actually that is happening to me since me moved to an old house in a town north of Barcelona. Instead of having the washer in the kitchen, like we used to, now we have it in the cellar, in a place I don’t normally pass by to notice the laundry is done.
So I started thinking about monitoring the washer to get notifications when the laundry is done. And since I was at the same time playing with ITead’s Sonoffs, which has an AC/DC transformer and a powerful controller with wifi, it looked like a nice project to put together.
Since I discovered the Sonoff I’ve been thinking about embedding it inside a switch. I started looking for old power meters, timers,… I had at home but the Sonoff is a bit too long. Why didn’t they design a square board? I event bought a bulky Kemo STG15 case with socket.
Next I decided to design my own board. It is meant to be the “official” hardware for the ESPurna project so it’s called ESPurna too. It’s opensource hardware and available at the ESPurna project repository at Bitbucket. I have some boards already for the first iteration (version 0.1). They are mostly OK but I’m already working on a revision.
But then ITead’s released their S20 Smart Socket. It’s the Sonoff in a wall socket enclosure. Almost 100% what I wanted. And at 11.70€ it’s hard to beat. There are other wifi smart sockets available, mainly Orvibo and BroadLink (an SP2 Centros should be arriving home anyday now) but ITead’s is cheaper and you can easily re-flash it. Just solder a 4 pins header, connect it to your FTDI programmer, hold the S20 button, connect the programmer to your computer and flash. Done.
OK, not so fast. Why would I do that? Why would I change the stock firmware?
The answer for me is a mixed up of philosophy and practicity. But you are right. Let’s go step by step.
I was not the first to arrive at the party but since I discovered the ESP8266 I’ve been enjoying it. Then I stumbled upon the Sonoff and dude was I amazed. They are cheap and so very hackable you cannot help buying them, tear them open and customize them.
Sure they are not CE or UL compliant, yet. My previous post about adding a custom RF module to a Sonoff HT got some visibility as it was published at hackaday.com. Most of the commentors there where concerned about safety measures in the device. The truth is that early Sonoffs looked more like products for the DIY market, not for end customers.
But ITead’s home automation product line is evolving quite fast. It all started with several Sonoff models (with or without RF, with or without temperature and humidity sensors, with or without AC/DC transformer) and the Slampher I’ll be reviewing it soon.