SonOff Low Cost Wifi Switches for Home Automation

One or two folks have questioned the security of the Sonoff app. I guess on the basis that it has access through your router/firewall and takes the WiFi creds off your phone or tablet during setup?
I have not however seen any vulnerabilities described and the process of passing your WiFi credentials happens when your phone is connected directly to the Sonoff module while the module is an "access point". It then restarts in "station" or "client" mode and connects to your WiFi. This would suggest to me that the creds are not passed to the module via a server in China during setup and I guess if it is well designed the Sonoff module need only establish some sort of secure key during the setup? That said how this stuff actually works is above my pay grade!

I bought a box of them for my own use and to sell on. I even figured my kid might try to move some at a car boot sale and get a taste for enterprise and business but few ordinary non-technical people seem interested. I have given a couple to friends, one in an extension lead (yes, the earth passes through the Sonoff case!) and she uses it on an electric blanket. She was for ever waking up 3/4 cooked at 4:00am with the blanket turned on, a simple rule in the timer schedule fixed that.

An other use I have for these is re-booting your home router. These can benefit from a re-start from time to time and the Sonoff is ideal. Again properly installed in a short extension just program the Sonoff to turn off for 1 minute at 4:30am every Monday morning for example. The time schedule is stored locally in the module so the relay will go off and then back on again once the module itself is still plugged in, QED!

Garry

Stoner wrote: »

Will it turn back on..?

Yeah, that is how it works with the schedule stored locally in the switch. I tried this and while the switch was in the middle of a scheduled switch off for 1 minute I pulled the WiFi down and the switch still followed the schedule and came back on. Handy for doing this restart job.

Hope this helps

Garry

Stoner wrote: »

Ikea have ceiling roses cw fkex and an E27 lamp holder for 3 euro.

The rose itself is large enough to hold the Sonoff

Well it is not a bad thing you post this now, a direction I think I am going.

I have cranked things up a step and have enabled an Amazon Alexa skill to control my Sonoff basic switch units. I will do a write up as soon as I get a chance because it is so simple and it works a charm. For those who sport tin-foil hats be warned: It is a skill that combines your ewelink account with itead and your Amazon Alexa.

In fact I was so impressed by the simplicity that I have ordered (some on back-order) T1 light switches and B1 colour adjustable and dimmable LED bulbs from itead.cc to add to my Alexa controlled setup. I research and post some info on the T1 light switches as they require a mains Line and Neutral. I will have to check regs etc.

This flies in the face of a lot of the work I have done at home putting together a custom setup largely based on ESP8266 controllers (same chip as most Sonoff) controlled by Node-Red and MQTT. That said I will be keeping my custom setup and will be using some Sonoff Pow switches hacked with the Tasmota firmware to track and log power usage on certain circuits such as the washing machine. Aside from the power usage stats it would be very handy for MrsKyo to get a push message when her machine finishes a spin cycle. **please don't flame me with the misogynist stuff, she loves her washing machine and actually gets upset if I touch it beyond repairs!**

I think a new thread on Alexa + Sonoff (or other products) for home automation may be interesting?

So far the posts on this thread have looked at these very handy little WiFi switches from a couple of angles. The stock app from Itead does work and seems both powerful and robust. I have a couple of the Sonoff basic switches hacked to work on custom firmware called Tasmota which is supports programming over the air (no USB to serial required after the first flash, firmware updates, WiFi and MQTT setup via a http page that the device hosts on the ESP8266 via a web server, some power and flexibility for a €5 device and Itead support the hacking community too).

Despite having lots of ESP8266 devices doing all sorts of automation in my home already and on a custom MQTT/Node-Red setup I couldn't help notice the "Works with Alexa" on the Itead site while I was ordering parts. For the pig iron a couple of months ago I put Amazon Voice Service on a Raspberry Pi just to have a mess with this. Having all the bits to have a go, well it made sense to try it out!

Let's assume that if you are going to try this you will have tried Itead's ewelink app or Amazon Alexa or both. I have never set up an Echo or Echo Dot so I should perhaps not go through my setup which was on the Raspberry Pi so different.

Once you set up the ewelink app you get a list of your Sonoff devices as below:



To have a go with Alexa I just paired up a new Sonoff Basic and gave it the name "Test Switch" in the ewelink setup. You can change the name of a device or group devices once they are paired.

Mine may be different to your setup if you use a genuine Amazon Echo or an Echo Dot like this one but in any case there is plenty of support getting started:



Essentially once your Echo is set up and working you need to log in to your Amazon account and find the "Skill" which Itead have created to enable this service. Do a search using the search phrase "ewelink" which may bring up two results. The skill that you need is the newer one from Itead called "eWeLink Smart Home Fan" so select this and if you see a button to enable this then click to enable.

The rest of the setup is so simple that I recorded a few seconds of video. Simply ask Alexa to: "Discover Devices" and once this is complete command your Sonoff Basic switch using the name that you gave it during setup, simples!



The mobile phone in the video is there just to show that the switch is changing state in the app. The green indicator on the switch on the stock firmware is just used for WiFi status.

This is the Sonoff Basic switch from Itead but is just one of a family of devices that are controllable using this Amazon Skill. I have back ordered some T1 switches and some B1 lamps which I am keen to try out with both Alexa and my own setup. There is a decent tutorial on setting up the voice service HERE

I have no doubt that other brands and products work equally well, I have no experience trying Nest or Hue or any of the popular units. Where Itead win for me is that they cost so little, this switch in the video is currently €4.25 or so, less than a pint!

Hope this helps or inspires some of you to have a go!

Garry

Nirvana999 wrote: »

I wish I understood all the technical stuff you guys are discussing.  I have a home in Ireland, but live in the USA and travel home only infrequently.  I want to be able to control my oil fired central heating from the US.    At present  all I have is a mechanical timer ... On, Off, Timed.  I have it set to timed until I get back.  Obviously if there is a power outage the timing goes awry.
Will a Sonoff work for me?  Can I relatively easily unwire the old timer and install a Sonoff, control through the wifi by my phone in the US?  Is there any temperature control that I could easily attach so that I don't have the heat come on in winter if Ireland is having an Indian summer? Any help, most appreciated.  I live in a fairly remote location so organising an electrician for the short time I'm home is problematic.. so need to be able to do this on my own.

Hi Nirvana999,
Quite a few variables there, some only you could answer really with regard to your ability wiring up, setting up etc. There are hundreds of videos on YouTube showing how folks wire these up so maybe have a browse and satisfy yourself on this point first.
Next: The switch should be able to do everything your standard mechanical timer can do in terms of switching. It does rely on being paired to a Wireless router in a WiFi area so that instructions can be sent to the device and so it can re-synch with the time when there has been a power cut. If you don't keep a phone/internet connection permanently on at the house then the switch won't work.

With regard to temperature, surely running the boiler simply as a frost protection is all you need when you are away. Comfort temperature is considerably higher than you would need for frost protection and much more expensive to boot so if I were you I would:
Run the water thermostat on the boiler very low so as to just warm the radiators.
Run the boiler every day at this low temperature to keep it ticking over, silt free etc.

Beyond that I am not the one to advise you! I am not a central heating expert but logically this strikes me as the direction you need to aim.

Garry

Look what came in the post

Sonoff Pow has a shunt resistor on the PCB, will be set up to measure power use on certain devices, just to know sort of thing. Any suggestions welcome.

I have a 4ch pro with a 433Mhz remote. I may flash with Tasmota or similar firmware and experiment with this as a boiler/zone controller for home heating. The reason I got the remote version is Halloween. I had some ESP8266 based spooks last year (https://youtu.be/YeopeXz1d0E ) but would like to be able to prompt stuff from a key fob for a laugh before I wipe the Itead firmware.

I have a couple of T1 switch plates to try out. One is a single for my teen age son's bedroom. He actually agreed that a scheduled turn on time for his bedroom lights would help in the mornings. Let's see how long the novelty lasts! I also have a two gang switch plate which I may put on the hall/porch lights. I have an LED flood light which is very white and very bright so have this on a PIR sensor only. A soft coloured porch light with physical and remote control with a schedule/timer option would be less hostile looking on the front of the house I think!

Aside from stocking up on standard 10A Sonoff switches I got an other 12v dc powered Sonoff. I made one of these up into a little box with a barrel plug on a flying lead and a chassis socket. This makes a neat in-line WiFi switch that I can schedule to reboot the home router every week or so. Seems to help our basic router with faster dhcp connections and more reliable streaming of the wired cctv server.

Lastly I got a B1 lamp which is a fully adjustable RGBW LED lamp to try out. I'm interested to try this to get to know the technology better. I have a bag of neopixels (indevidually addressable LED's) which I have only done some very basic experiments with. I would like to do some programming of neopixel strips over the winter but having a working app (eWelink) to mess with first is no harm. I am pretty sure Pete Scargill has done some hacking of the B1 lamp so I must go have a look!

Now to order some spare time...

Garry

air wrote: »

I've been considering the switch plate. What are they like from a tactile perspective? Is it easy to find the individual switches blind?
I bought a 4Ch pro myself recently, didn't even realise it had RF, still in the box for now.
Did the pro version have RF from launch?

I'll let you know air. Didn't do any more than snap a pic so far, agenda full for the day. They do have a dim blue LED apparently but again no hands on yet.

Garry

Metric Tensor wrote: »

How much did it set you back all in?

I'm jealous!!

A sniff over €100 plus shipping, from memory about $120 which isn't really a huge amount of money for the functionality there, just IMO...

air wrote: »

I've been considering the switch plate. What are they like from a tactile perspective? Is it easy to find the individual switches blind?
I bought a 4Ch pro myself recently, didn't even realise it had RF, still in the box for now.
Did the pro version have RF from launch?

4ch Pro:
I think it is a whole different animal to the older 4ch. It appears to have RF by default which is on the main PCB, the ESP8285 module is re-flowed onto the board. There are lots of micro dip-switches, one bank covered with capton tape so I will have to do some reading. I am sure it is configuring interlocking and such like. Consider a roller shutter application for example, it would be exciting to say the least if you pulled in the contactors to raise and lower the shutter at the same time!

Switch Plate T1:
The switch plate is quite tidy, has a glass front face and the Sonoff logo in "chrome" silver so not ugly. The capacitive switch is on of the now popular 3.3v modules all over eBay and AliExpress and Banggood. These have a very good sensitivity level, easy to use but not trigger happy. The touch module has de-bouncing built in so the switch is "numb" for about half a second after it is activated making it easy to use. Only the lightest touch on the dimly lit circle is all that is needed to trigger. The switch footprint (under the glass) is 15mm wide and 18mm tall and while touching the corners of the switch works it does reject wildly off target attempts!

Technical/Safety:
If you don't know what you are doing then get an electrician to do the installation. It is necessary to pull a neutral to the back of the switch and if you didn't know that there is no neutral there then get an electrician. It is also important to use a neutral on the same lighting circuit as your light as an imbalance on the Line/Neutral on this or the donor circuit will cause nuisance tripping of your circuit breaker. If you don't know why this might happen then get an electrician to do the installation! Hmmm, a bit of a pattern there :rolleyes:


Here's a little snippet of mobile phone video using the switch plate.


My only less than fully positive comment is the brightness of the WiFi status LED! For a daytime indicator this is positively visible, for a bedroom, well it is like a floodlight! What you see there in the video has one layer of blue PVC electrical tape over the LED already. I may tone it down a bit more as the light switch is very visible (unlike a traditional mechanical switch) in the dark but that indicator... just too bright!

Garry

air wrote: »

Chances are good that your lights use a lot less than 2A, especially if you've upgraded to LED. The biggest issue you'll face is needing a neutral at the light switch.

Well on that subject, power and amps, I stuck the Sonoff POW into an extension lead and plugged it into our 10 year old washing machine. Was curious to know what sort of power this old machine used.

The POW interface on Itead's eWeLink is actually quite neat. It gives a current power on the screen full of Sonoff devices. You can tap on the Sonoff POW row of this screen to get richer data which gives you the same power output with two extra buttons. One button allows access to a kWh counter, operated like a stopwatch so this is what I used to see the power consumption. The other button reveals a graph of daily, weekly, monthly consumption totals for the POW unit.

Here's a couple of screen grabs from the phone. First one is the max instantanious power as the element heated the water in the drum, North of 2000Watts was a bit surprising.





This one is the total power consumed by the machine from the start to the end of a regular 30°C wash



Of course it does everything that any of the Sonoff switches do, has a timer, scheduler and is compatible with Alexa and Google. It costs €10 which strikes me as being ridiculously cheap for what it does? I will probably leave this on the stock firmware for the moment but depending on applications I may add it to my Node-RED home automation at some point.

HTH

Garry

@bluemachaveli: from your photo I am guessing you are re-flashing firmware? The ftdi board is a hint here, but if you are then you're free to program GPIO14, conveniently broken out through the extra pin of the programming header as an additional input or output. Do this by connecting whatever you choose between this pin and gnd.
For a second GPIO: If you are re-flashing then you no longer need the factory functionality of the stock button. You can simply solder to the two switch pins closest to the edge of the pcb and again program this (GPIO0) as you choose in your new firmware. Even if you are using the stock Sonoff firmware this input can be remotely wired to any kind of normally open pushbutton contacts.

Of course this begs the question; why would you use a Sonoff at all of a NodeMCU or Wemos D1 Mini for example will program up the same with your custom firmware, break out more GPIO and even an analog channel for sensors?

To my mind at the current price of just over €4 for a basic Sonoff which:
1. Comes in a plastic case
2. Has its own mains - dc switching power supply (pretty well implemented too)
3. A reasonable mains powered relay
4. Comes with a decent firmware & app for non "hacker" deployment
5. Readily accepts many proven and maintained firmware platforms
6. Can be programmed by you, your way via Arduino IDE
7. Comes with a programming header
8. Has additional GPIO for re-flashed firmware

And is just a lot of function and option for the money. Consider the price of a pint as a yardstick ffs!

PLEASE BE AWARE
That some of the best features from above make the Sonoff dangerous as a development board. Never use the internal power supply powered off mains while the unit is open for programming! Remember that the relay is permanently connected to the live phase of your mains connection and the mains neutral is permanently wired to the output; this is NOT a volt-free relay contact!

There are other things you can do to bling up or pimp your Sonoff like flash memory upgrades. This makes a big difference if you install the OTA (Over the air) programming components. These allow you to re-flash your Sonoff and at any time in the future to tweak, modify or replace your program wirelessly over WiFi, so handy if it is deployed remotely.

Jonathan Oxer of the SuperhouseTV YouTube channel pot this blog post up with lots of handy text and images and a link to a very insightful video here:
http://www.superhouse.tv/21-six-sonoff-secrets/

Hope this helps

Garry

wexfordman2 wrote: »

Hi,

Does the 4ch pro work with Google home out of the box ?

It does in so far as you have to setup the connection to Google Home. I have only used Amazon Alexa to control the Sonoff products and it is as easy as installing a recipe on the Alexa control panel. I guess Google is as straight forward.

The eWeLink app does work with Google Home and the 4ch Pro. This should help: https://www.itead.cc/blog/sonoff-work-with-google-home

Garry