Sonoff TH10 and TH16

You will have seen me write about the excellent Sonoff ESP8266-controlled mains relay switching devices in the past and I went into great detail as to how to program them using the HC2016 software, the only caveat being they don’t have enough FLASH memory for OTA (well, not with my software). Oh yes and I HAVE added that “button control” that people asked for.

Well, here are two new boards – the Sonoff TH10 and TH16 – if you look on their website – full information including schematics etc. are freely available.

Itead Sonoff TH10[6]

Before we start – here are my previous blog entries Sonoff

Slampher and Sonoff
More Sonoff
Even More Sonoff
Sonoff to Mains Block
32Mb ESP01 and Sonoff

Compared to other boards, several of us have discussed that the Sonoff boards are well made with good clearance on tracks for mains power etc. Some doubted whether their small relays would truly handle the loads claimed.

Well, it looks like ITEAD have taken this on board as I’ve just received both TH10 and TH16 modules.  As far as I can tell the only difference is that the TH10 has a 10 amp relay, the TH16 has a 16 amp relay.

Side View of Sonoff TH10First impressions? Solid. They are bigger than the original Sonoff modules (which I use on a daily basis for controlling lamps etc) but also  much more substantial looking – the programming button is much easier to access as it is intended to be used rather than looking like a reset button.  I’ve made good use of this as an output toggle (which also works on the previous Sonoffs).

As usual I’ll leave it up to others to tell you what you can do with the Sonoff software – first thing I did was to reprogram the boards to handle my own software.

So – the output control is identical to the older models – but they’ve also added in a temperature port. They have very kindly made the input port compatible with my software (see settings below) and options are temperature only using the Dallas temperature sensor which they can provide on a waterproof lead complete with stainless tip – or the DHT22 which also handles humidity – I’m pleased to see they did not use the inferior DHT11 which isn’t that accurate.

PCB for Itead Sonoff TH10

So – see the original article – you’ll see there how to program up the board – this time – the ground and power connectors are blindingly obvious on the end of the board – that’s 3v3 not 5v – I got away with using an FTDI at 3v3 but you may want to consider a proper 3v3 supply for programming.

Itead Sonoff TH10

If you set wifi_button to 0 – sonoff to 1, temp_type to 0 (Dallas) or 1 (DHT) and temperature_port to 14 (these are non-volatile)   you will be able to control the output on out12 (i.e. out12:0 or out12:1), you will be able to read the temperature AND you can toggle the output on and off with the external button on the Sonoff!

The CE and ROHS stickers should keep those who care about such things happy – the important thing for me is looking at the PCB around the mains it is clearly obvious that thought has been put into this. Well done.

Sonoff connectorsOh yes, the FLASH – like the unit before it – we’re looking at an 8Mb FLASH – that is 1MB –  I don’t really support that for OTA though everything works except OTA. I am pretty sure that like other boards, this FLASH if you really must, can be replaced but be warned my soldering isn’t bad and I’ve done lots of Sonoffs, ESP-01s etc – but the little tracks came clean off when I tried it on one of these boards, immediately trashing it – so do so at your own risk.

As for the push connectors for mains in and out – not everyone’s cup of tea and I did have a chuckle that they’ve gone to the effort of avoiding using a screwdriver for the cables – but you have to use a screwdriver to get the cover off !!!!


111 thoughts on “Sonoff TH10 and TH16

  1. Just a quick look but that does not look like a CE mark, It looks like the so called "china export" mark. With the CE mark the C and E should form circles that over lap.

    That said I now have two of the old one running your code and they seem to be rock solid. un-plug them and plug them back in and they connect and start running first time every time.

    I'm quite happy to run these at home as the board has better creepage and clearances then some CE marked products I've looked at.

      1. I don't put much store in CE marking - it means very little as you can easily self-certify and as you say there is China engineering. You can buy the stickers cheap and for small batches CE testing is... well, don't get me started. One look at these boards and you can tell they've put thought into them - the power area compared to some oriental power supplies is well thought out.

      1. HAH! I knew I'd seen that name somewhere. Can you check your blog. I'm having a go at your Sonoff code and I've managed to get as far as the opening screen on PlatformIO - and downloading your project. Anything further than that is currently escaping me... a starter for 10 would be appreciated.


    1. CE marking is not, but if the product really passed the standard safety tests, it is.

      For us hackers it doesn't matter much, but if Itead wants to sell their products to as a consumer product within the EEC, they need to have CE certification passed, either by them directly or by the importer, as customs may require proofs at any time.

      And be sure that if your device catch fire, the insurance company will not pay for your burnt house if they can prove that it may be the cause 🙂

      Again, this is a risk that we can tak as hackers, but we know what we are doing, are we?

      1. I think they'll be managing quite nicely regardless - our market is but a tiny corner - and as you say enthusiasts - and I do think that is where they are interested - after all you could not put programming and other connectors onto a product for the mass market most of whom would not know a programmer from a hole in the ground. I doubt VERY much if a British insurance company would miss the opportunity to rubbish a Chinese product REGARDLESS of what markings it had. "And which reputable firm did you buy this from, sir?" - "China" - "Oh, I'm afraid we don't do China". Trust me - I've been there.

        Frankly I'd be more worried about people poking wires into a connector 🙂

        1. And... while I think about it - I doubt VERY much if the mass market read this blog 🙂 So I'm assuming I'm talking to people who are (a) enthusiastic and (b) have something of a clue how not to get electrocuted.

          (Disclaimer: If anyone electrocutes themselves, I don't exist - you only imagined reading this blog).

          1. i've just spent the last few years getting the CE marking up to date for a range of products from medical to machinery. only issue we cant see it the creepage and clearance inside the switch mode supply transformer. the PCB etc goes out the window if the transformer is badly wound and insulated.

            But i'm more happy to run with them than an imported psu that you can't open.

            anyway I've a timer that states that it should not be left unattended! so not sure why you would use it if the manufacture don't think it's safe!!

      1. Oh and the output is on GPIO12. What I don't understand is that in the middle of the board is quite a large 0.1" pitch connector - or rather the filled in holes for one - and not much attached. I wonder why they didn't take the opportunity to put the other IO onto that connector. Still - it's a step up. I'm just so annoyed that I messed up the tracks on the FLASH chip when trying to update.

        1. Hi Peter, did you use a hot air setup to remove the IC?
          I purchased an ATTEN 8586 a few years ago and it was the best investment I've ever made. So easy to remove IC's or other parts from boards without doing any damage to the PCB itself. Oh and it doubles up nicely for heatshrinking jobs too 🙂

  2. They look good, but I've just had a sonoff die after only 2 day of operation. Mains input section has gone. powered from the program port and all's well.

    Now I've got to see which bit has gone too much talk of reliability of late!

  3. I had a couple of Sonoff Dual's arrive yesterday. Very impressed by the casing and push terminals - I think they're quite an improvement over the screw terminals on the original.
    Does anyone know how to pull GPIO0 low to load new ESP8266 firmware via serial? On the single channel version, the push button does this - but it doesn't seem to do it on this one.
    Any ideas?

  4. Can anyone post a step by step description of how to put the TH10 into flash upload mode? I've seen a couple of methods posted, but have not been able to get the board into the upload mode (I have previously been successful doing this with the other itead Sonoff unit, but haven't been able to do so with the TH10).

      1. Oh, sorry - I just assumed that was common knowledge. Yes, the button held down with the power off lets you program them. From there on it can be used as a toggle for the output (well, it can on my software) and also for web access... but I've not made that last one the default yet, I think it defaults to GPIO2 for web setup for our own boards. Pity there isn't something that would uniquely identify the SONOFF board.

      2. Thank you, this worked great. Unfortunately the itead folks got a bit more clever with this device. I was able to download my Arduino Sketch, and it attempts to work, but it appears the bootloader on this device is set up to load the itead configuration firmware before my sketch loads. Other devices, such as the Sonoff relay board don't do this. The net result is that the device comes up in AP mode before the sketch attempts to start the WiFi server in my sketch. Looks as though I need to fully erase the memory in the ESP8266. Can someone point me to a method of erasing the memory that still allows me to download a sketch (doesn't "brick" the TH10)?

        1. I'm having trouble with this David... unless I'm reading your note incorrectly - it is suggesting that somehow, sometihng iTead have done is interfering with the flashing process. Not buying it. That process is set in ROM on the ESP8266 and cannot be altered (if it could I'd be changing that 78k debug output to 115k).

          Ok, so - it may be that you need to PROPERLY clear the device first in case there is something going on at the top end of the setup - recent versions of the SDK DEMAND that this is set up - earlier versions did not. Reading through my setup article might provide insight.

    1. Hi Be aware that the sonoff touch requires a neutral connection at the switch. Whilst this is normal in US houses it is unusual in UK houses due to our solid walls leaving restricted space for wiring and pattress depth.

    2. Same here in Indonesia. No neutral in the light switch sockets.
      For this reason, I have chosen to use these with custom made enclosures. A lot more expensive of course, but no batteries and wiring required. As I live in an apartment, I don't have many switches to deal with an my Amazon Echo takes care of the front room lighting and sockets. There is a module for the Pi that plugs into the GPIO port and there is a Node-red module to decode them.

      1. No neutral here in Spain.. I started looking into this and the more I do the more I wonder why Britain came up with this live-neutral system in the first place. I know why we came up with the ring main - to save copper!

    1. This is new to me - and hence I've not had a chance to look at it - I'll drop ITStudio a note and if they ship of a sample I'll have a look with a view to modifying the software.


  5. Good afternoon, everyone. I just opened up my new Sonoff POW, and, as exlected, it's a fine little switch. The on oars relay is rated for 1 hp at 240v, so I will likely give a solitaire feild test on my big dirty .5 hp pumps soon.
    I'll use one for each pump, plus a TH to monitor the water temp.

    Meanwhile, I have it measuring the power useage of my Sonoff controlled fishtank.

    Ivery been focusing on the hardware, and have been using Ewelinks, as it meets my needs.

    As for the power sensor, I was hoping I could jumper in a nice closed core current meter, but I'll need to trace it out a little more before I start cutting it up. The good news is the 16A relay can likely handle all but the most industrial applications.


    1. I have all the new Itead devices on the way, should be here toward the end of October and I'll tackle all of them - so the more info folks can provide beforehand the easier it will be for me 🙂

          1. I received a sonoff pow today and I'm trying to flash it but I believe the button may not be connected to GPIO0.

            Have you managed to flash it? If so, would love some pictures/instructions on how to do it!

  6. I just purchased my first sonoff with another on the way. I do have a question regarding the timer function native to the device. Are the times stored on the device or is it necessary that my IPhone be in range for the timer to work?

  7. Thanks Pete for this great blog.

    Thanks to your direction I've managed to flash a webserver on a sonoff TH . However I'm unclear:

    - how I can read the temperature / humidity from the ESP 8266 : which pin? Which configuration?



  8. Hello Peter,
    Thank you for all the work you've done and explain how to flash the sonoff device.
    I have one question which I can't find the answer anywhere, although should be simple!
    I have the sonoff TH10 with ESP Easy firmware, the ip is:, if I want to turn on the relay, I use the following command:,12,1
    which works fine, what I'm struggling to find out is how do I read the temperature/humidity sensors which are on gpio 14, and I didn't manage to find any answer.
    Thank you in advance

    1. @radu: i think you think the wrong way, with ESPEasy you do not read the sensor date, instead ESPEasy does send the sensor data to somewhere else...

      see pictures for my config:

      under config you can define where to send sensor data, e.g simple http get request or mqtt

        1. Hello krikk
          Thank you for your answer, after all I've found how to get the data from the relay, it's pretty simple, but not documented, all the details you can get them with 1 call and you receive a JSON answer, the request is link is very difficult: relay-ip:relay-port/json 🙂

    2. Hi Radu,

      for me it's the other way around: I have the temperature working, but can't switch the lamp. Using the same command, and I hear the switch clicking ,but nothing happens. What is your config for the switch?

      1. I did but I haven't got an answer.
        I was thinking that maybe someone with more electrical knowledge than me can explain why.

  9. Hello,
    Thanks for having this blog it seems very useful and informative for "automation folks" which I'm planning to become myself as well. I'm (very) new to sonoff and trying to find an answer here with no success. I like to figure out how to set up the external 2.5 mm plug on the TH10 to control the switch instead of being triggered by temperature. My plan is to plug in the original wall switches to keep the traditional setup and add wifi option with the sonoff. I've seen a video on youtube and the person demonstrating it claims it is possible to do with the original firmware. When I plug into the 2.5 mm the sonoff shots off, tried on several units same issue. Please advise what to do. Thank you so much!

    1. Well you would have to write your own software of modify some existing software. I can't remember offhand but the temperature sensor simply feeds a port bit - will no doubt have a pullup resistor so likely all you need do is chip out the support for the (I think) Dallas temperature chip - and monitor the input to turn the output on or off depending on the state of the input.

  10. Could use some help...I'm not a technogeek. I want to monitor room temperature via wifi/internet and be able to see it on my phone. No switching. No hardwiring into appliances or a wall desired. Can I somehow plug in the TH10 or TH16 (?which should I use) into a wall outlet and have it report a room temperature to me? If so, how? Do I have to have 3 dangling wires screwed into some plug thing to plug into an outlet, or is there something more aesthetic I can buy to do this job? Thanks.

  11. Hi AW,
    If you're just after monitoring a temperature reading via a simple mobile phone interface, you could consider "Blynk". This is a clever little platform with an Android and Apple iPhone App which, with a small amount of code, an ESP8266 (powered via a USB charger or similar) and a DHT22 or Dallas DS18B20 temperature sensor will give you what you need with very little technical knowledge required.

    Above is an 'instructables' article describing something similar to what I think you're after but there is an active discussion forum/group at the Blynk web site

    I recommend Blynk for your requirement as it sorts the internet/mobile access side of things and the sensor all in one go. There are other options available without using Blynk but these may be more convoluted especially if you're not already familiar with ESP8266 etc.

    Rather than using a 'vanilla' ESP8266 requiring 3.3v as per the instructable, I'd recommend looking at a "Wemos D1 Mini" board as these have onboard Micro USB interface for programming and for powering the device, so once programmed you could just stick it in a little ABS enclosure and power it from a USB power supply/charger via a standard microUSB cable.


    1. Hi Darren - I'm guessing you've never gone through my earlier posts. I took an intense interest in Blynk and had many conversations with the designers - it is pretty - however - most of these systems show little interest in Node-Red, preferring to work with every interface known to man and hence limiting their overall capability and stretching their resources - if they would merely concentrate on producing an all-singing API so we could roll our own thing - but sadly - no - which is why I've all but abandoned all of the alternatives in the hope that Node-Red Dashboard will continue to improve - indeed again looking back through posts in here you'll see how to add all sorts of impressive widgets to Node-Red Dashboard, far beyond the limits of the existing graphing, dial and other interfaces. There IS an interface between Node-Red and Blynk which is 99% reliable but I could never make it 100%.

      Still - some of the Blynk widgets are great - their colour widget however is not and takes up way too much screen space. As you've brought this to my attention I've been back to their site - what has happened recently? Not a lot. To this day, Node-Red is STILL not officially supported as far as I can see so you're in the hands of third parties who may or may not choose to keep the interface going.

      1. Hi, Peter. I just left a reply to Darren, but your input would be valuable also. However, I'll admit I didn't understand much of what you wrote to Darren, since I've no understanding of what Node Red is. Again, all you guys have been great with your patience with my basic questions.

    2. Darren, first off, thank you for the thorough and respectful post reply to a noob like me. That said, I checked out the links and found myself a touch overwhelmed by what was there. I don't own a soldering iron, and I've never bought that white pegboard thing that you attach wires and such to.

      It looks like fun to learn, but unfortunately I'm not able to invest that much time relative to what I want to do.

      Is there any way to use Blynk with software programming of it to work with the already-made Sonoff TH10/16? That way I just screw in wires to the Sonoff, plug in the humidity/temp probe, and then program Blynk to recognize it and email me when the temp exceeds a certain threshold. Is this possible?

      1. Hi AW,

        Yes you could use the SONOFF with the external temperature probe and Blynk to do exactly what you require...but (there's always a but...) in order to flash the replacement firmware (Blynk software stored on the sonoff itself), one needs to solder 4 pins to the SONOFF board and then connect those 4 pins to a PC via a special USB device and some software on a PC. Its probably easier on an ESP8266 "Development board" instead of a Sonoff as you can buy SOME of them with header pins already soldered...and then you could use breadboard jumper wires (female to female) to connect between a DHT22 breakout board (with header pins also pre soldered). Many 'dev' boards have MicroUSB sockets which can be used to power the device but also to flash new firmware across however the SONOFF requires a separate USB to Serial device to update the software - this is something I have several of and use all the time but isn't something a 'noob' would have just lying around. Given your self confessed noob status, and the complications listed above, a Sonoff device gives with one hand and takes with another so it might be pushing it a bit.

        Your best bet might be be to get someone to do the soldering for you on the Sonoff and that would get you past the first hurdle. You could then learn the coding side of things with Blynk (if you are up for that). It would be a great opportunity to be brave and have a go yourself as it's more rewarding that way but I also appreciate there's quite a bit of learning curve if this is just a one-off.

        I have built and implemented several not dissimilar SONOFF / Blynk projects for colleagues and friends, providing the kit ready to "plug in and go" including bespoke software to do whatever is required (Remote temperature sensor and relay for remote heater control, Garage door control, Driveway gate control, timed outdoor lighting etc) so I would be willing to assist you more if necessary but that wouldn't want to totally remove the satisfaction you'd get by having done at least some of it yourself.

        Let me know if you need any more help and how much help and between us all here there's more than enough knowledge and helpfulness to get you sorted.

        1. AW - Re-reading your reply, it sounds like you need something a bit more 'off the shelf' so my last reply is probably not much help.

          The standard (chinese) software/firmware that comes with the Sonoff might be up to the job - you'd be in the hands of ITEAD and need their proprietary iPhone/Android app to be able to view the temperature etc but that would work "out of the box". It doesn't sound like it sends email alerts but it would show a temperature reading on your smart phone. I've never tried the standard Chinese firmware so can't provide any details on how it works (or how well) as the first thing I do is remove the standard firmware/software and replace it with my own (or someone else's) as I'm a geek.

          I'm happy to assist (offline) with a ready made turn-key solution if you're interested - it's all good fun this 🙂

          1. Sorry, I missed this comment, Darren. How can I reach you offline to find out more about your ready made turn-key option?

            1. Hi AW,

              If you click on my name to the left of any of my posts, my e-mail address is in my profile text.

              Have a good weekend. Sorry for going off topic, Pete et al.

        2. You ROCK. Thank you for your patient and thorough, albeit intimidating, guidance. Of course, the advantage with the Sonoff is the ability to simply plug in a temp/humidity sensor and you're good to go to see the info over wifi anywhere in the world. It seems such a minor thing to be able to trigger an email alert in the Ewelink app, but the developers I contacted have no plans to change anything in it. You're right, though...for a one-off, that's a lot of learning and I don't think I've got what it takes to do it. Still, I really appreciate the time and effort you made in coaxing me to try!

        3. Just a short addition but if soldering is the issue I have found it unnecessary on these devices. You can just hold a row of 4 pins in place whilst the flashing takes place (20 secs). After that further updates if necessary can be done OTA

  12. Hi Pete,
    Crossed wires maybe?. I am totally with you on node red vs blynk but for the poster "AW" who appears to just want a simple temperature sensor reading accessible by mobile phone it's a quicker solution to solder a DHT22 to a Wemos and flash Blynk on there. Quite different requirement and complexity to the great work you are doing with more compressive control systems, node red and your code Base.

  13. More news. So I just wanted a simple monitor for cheap that could send an alert if a temp exceeded a threshold. You can find them for $60 to $200 online. I scoured for something cheaper. Today, deep within Amazon, I found this, which looks like a kit thing put together by a coding group. Anyone know of it?

  14. And more news. OK, got the Sonoff TH10 and the temp/humidity probe. Total cost with an extension cord around 20 bucks. Cut the cord in about half and put the Sonoff in the middle. With this I can monitor temp/humidity, and have something (like a portable AC unit) switch on remotely (manually or in response to a temperature threshold) AND, something I didn't know, when the unit is switched on or off I get a notification on my phone. In other words, the email push I thought I needed is unnecessary, and the notification of a temperature threshold being hit is already contained in the Ewelink software. I can monitor temp and humidity and I get notifications when thresholds are hit, so all is good and MUCH easier than I thought it would be.

  15. Help

    Hello all i am very new to this and looking forward to my adventure

    I am using a Pizero and the image made by Andreas Spiess. It all appear to work.

    I have a few Sonoff Th10 and for the life of me i have been unable to find what firmware to load on (i have made the cable and get flash to them) to make Node-red communicate with them.

    I have post questions on his youtube channel but still awaiting a replay.

    I have looked through Peter's massive blog and still cant work out what to do. and searched the web and found many FW but i cant get any to work, some when checking the arduino code when adding in ssid and PW do not complile. I have loaded many libraries but still cant get past the compile check, some also are looking for other ****.h files which i have not found

    My Pizero works well thanks the peters and andreas hard work. I can SSh into it.

    I have played around with node-red and Peters BigTimer and that all appears to connect the the Pi in the debug window.

    I would like to use OTA updates if possible.

    I have purchased some larger memory chips if i need to replace them. but i think from looking at YT vids things have moved on.

    All i am try to do at this my starting point is to be able to turn a small hall way table light on and off.

    I also have an Echo Dot and would love to progress on to making that follow voice commands to turn it on and off.

    If anybody can link to a firmware that i can try and upload to my sonoff it would make me a very happy man as i feel like throwing the whole lot out of the window at the moment 🙂



        1. I use my own code aside from the Sonoffs (for which I use Tasmota - I have a wide range of peripherals in there and plenty of room for expansion now I've given up on the old ESP-01s. As far as I can see the ESPEASY software only has support for a tiny number and variation of displays - for example simple i2c 2 liners - and one type of OLEDS. You might want to take a look at my WORD manual...VT-100 mini-terminal, several types of LCD and several ways to connect them etc.

      1. Ok thanks. I have a Pizero running Andreas Spiess PiZero image. which worked very well. Thank you for that code Andreas.

        Nodered runs and i can see Peters Big Time. The Mqtt looks like it is also working in the debug window

        My issue is i have been trying for a 2 weeks trying to find a code to load on to a SONOFF TH10 to be able to let nodered turn it on and off.

        I can flash the firmware in a sonoff so thats now no problem to do.

        All the codes that i have downloaded and tested have failed. To be far this is very new to me, but i have done loads of research but still i fail.

        Even the code published from Andreas fails as i can find to files he refers too.

        The code that he published is:-

        I cant seam to find the correct AsyncMqttClient.h to download. all i am doing is searching in google and loads of various one appear.

        And also this part

        #ifdef useCredentialsFile
        mySSID = " ";
        myPASSWORD = " ";

        as i can find the credentials.h file i deleted the # lines and filed out my ssid and PW but it still want compile

        I changed the code to
        # define mySSID = " ";
        # define myPASSWORD = " ";

        but still no joy.

        looking through the code, woo that's sounds like i know what i am doing NOT, as long as i following his YT video all should be well.

        Then once it works i can learn how to change the topics, feedback etc

        Any idea what i am not doing correctly.

        I have also found a channel on The Beginner's Guide to Home Assistant - HassIO

        Do you think that would be easier for a novice to get on with, though i like Peters and Andreas channels and websites and feel i should solder on with this.

        Thanks in advance

        1. I now have it working.

          I am not able to get into the node-red dashboard it's asking for log in details. Tested all the ones I have from the pi image that I used but no joy

          1. If you installed the script from scratch - then the username for Dashboard is "user" and the password is the one you gave it. Under other circumstances - other software, non-standard setup, I can't be of help.

            1. Peter you are the man. I have logged in ok. Now the fun can begin. It's been a long two week struggle to get a sonoff to work but now it does happy days

  16. WARNING ABOUT 16A Sonoff Devices.

    I bought some "Sonoff POW 16A" devices in the recent Banggood Sale. These are labelled on the carboard box and the plastic ABS case as "16A" but when you open them up, the relay is a 10A model. On one of them it was clearly obvious as 10A and in another, there was a white sticker obscuring the 10A markings.

    Just a heads up before anyone loads up their Sonoff with 10+ amps. One should always take chinese wattage ratings with a pinch of salt and divide by at least 2 anyway but given there's a 10A and 16A option available, one would expect the 16A models to have beefier internals, not just a different number printed on the casing!

    1. This subject has come up before - Darren - can I suggest you send an email to the company and tell them that using a 10 amp relay and claiming 16 amps is simply NOT acceptable.

      Personally I would not go up to even that limit with these devices having used many Sonoffs. Perhaps 8 amps max - less for an inductive load? Even then that is 2KW....

    2. I may have overreacted, but am equally confused...

      Under the white sticker it says: -

      10A 250VAC and some symbols
      16A 250VAC
      10A 250VDC and different symbols

      I am guessing it may mean 10A continuous and 16A peak but the documentation and the product page when they sell these does not warn you about that. The leaflet inside the Sonoff box even shows a beefy heater being plugged into one.

      I'm not sure I'm feeling that confident and have informed Banggood (but I'm not expecting anything...)

      The above findings are the same on 3 out of 3 SONOFFs that I ordered. I ordered 2x TH16 (with the jack socket for a Dallas sensor) and 2x 16A POW. All the same under-specced relay.

      Admittedly, it's a slightly bigger relay than the small, basic SONOFFs, but that's not saying much as those units are pretty weedy inside.

      1. In the meantime I've brought this to ITEAD's attention and hopefully someone will comment. If it is a relay meant to be used at 10amp continuous and 16 amps peak then the box outside should also make that clear - indeed - I'm not even sure if most members of the public would have a clue what 16 amps peak means..... normally an appliance will quote either continuous current requirement or more likely wattage. Sadly wattage is useless here as the amperage is what matters for these relays.

        1. Thanks Pete, hopefully collectively we may get a response from ITEAD/Banggood. I like ITEAD's products and innovation, but they just fall short of being brilliant with 'niggles' like this.

          Most members of the public won't open the unit up as when advertising them for sale they say that you won't get support if you open them up. Odd really considering that they don't exactly discourage the use of 3rd party firmware etc.

          1. As in this case, Banggood are just one of many suppliers, we really do need clarification from Itead. They have my email but of course they are asleep right now in their part of the world (I think).

            1. Very true - the suppliers will just be punting out whatever ITEAD's documentation suggests. Have you liaised with ITEAD directly before? I know you regularly receive evaluation units from various parties, but wasn't sure if the ISonoff kit came from ITEAD themselves or a third party...

      2. as said by Peter, these concerns should be addressed to itead as manufacturer, but on the other side banggood is very good in refunding if you have problems, never had an item which was faulty and was not refunded or replaced... while with aliexpress recently this became a lottery...

    3. Hi Darren,
      Thanks for your feedback, we checked our products in the warehouse, it's ok.
      We use the 16A relay as we wrote.
      Please check the picture below, you can see the relay is 10 Amps DC and 16 Amps AC, please tear the white label paper, and check your product again.

  17. Hi guys
    Why are you trying to translate VDC and VAC to average/peak when it clearly means continuous and alternative currents
    Most relay, switches and devices with physical contacts have different ratings in DC and AC. Even the human body deals better with AC than with DC. This is related to electrochemistry as with DC, oxydation comes with lower currents (if I remember).

    Or may be I didn't understood your point and in which case I apologize for my wrong comment.

    1. The issue has been clarified by Itead as promised, in here. However, Barbudor, in my case I was not comparing DC and AC but simply saying that many electrical appliances have peak currents - for example, a 2KW heater element - let's say for the sake of argument it's average power consumption when hot is 2KW, will consume more than that when cold. I assume filament lamps do that (if anyone is still using them) but of course over a much shorter period. From a perspective of wear and tear, for my own purposes, I would never use, in this case a 16 amp relay with a 16 amp load - I would always leave some margin. Of course where this leaves us depends on the country - in the USA on 110v, 16 amps represents around half the power it would if 16 amps were in use in the UK at 220v.

      Given the clarification that the relay is 16 amps - and ASSUMING that the PCB tracking is up to the job, I'd be happy in the UK (220v) with using a 2KW load - but that's just me.

  18. I also received a reply from Banggood. Apparently I misunderstand the item, and maybe I do but the web site listings due rather gloss over the issue and not suggest a continuous max load to go with their (questionable) 16A maximum...

    --- Banggood reply as follows ---

    Dear Darren,

    Thx for your order NNN and NNNN.

    Maybe your misunderstand this item.

    Its max power is 3500w(16A), that mean the max current it can load is 16A but this status cannot last.

    Generally speaking , when you use it, the load current is lower than 16A.

    So this item is safe, you can use it without worry.

    By the way, this item has a CE certification.

    Best regards,


  19. Hi, just reviewed this switch, you can extend capabilities of higher current, replacing actual relays with OMRON brand. As we know, OMRON has been known for many years making good equipment. We can upgrade this to 20A, but we need to make PCB tracks thicker that actual are, to prevent burning/heating
    Search Google for that part: G4A-1A-PE DC24, it's 20A relay, controller by 24v Voltage, not bad. For testing and interest, I'll order one piece, to check if this works for me... An of course, one omron relay costs approx the same price as whole device 🙂 So, any questions about quality of OEM relay?
    I'm not sure, does current measurement will work properly if you upgrade relays.
    I have also mentioned, that you must change power terminal connectors with the type where you can screw cables to it, not just pressing fixation.

  20. hi,
    I want to control multiple electrical appliances based on temperature and humidity. Can I connect sonoff TH16 with Sonoff 4CH to control more than 1 electrical devices for my greenhouse.?

  21. Would you advise using the 16amp th16 on 1500 watt non fan heater in the UK 230v?

    Or should I avoid trying to using any wi-fi switch with heaters?

    Confused as the documentation in the box shows a picture of a heater/fan being used.

  22. my heaters has a pilot wire connection below, could I use 240V (live & neutral from another feed separate to heater) into Sonoff th16 input and then connect the black wire to output on Sonoff device so only controlling low power 100mA?? See blub from spec sheet about pilot wire?

    Pilot Wire Connection
    The BLACK control wire is designed to carry a signal from slot in or wall mounted Dimplex programmers. If, however a programmer is not being used, the pilot wire should be isolated in accordance with the current IEE Wiring Regulations.
    IMPORTANT - DO NOT connect the BLACK pilot wire to earth. Care should be taken with the installation of the pilot wire(s) as when switching to background (set back) they become energised at 240V although only at a current of less than 100mA. In every case a suitable means of isolation must be provided for the pilot wire and marked to indicate that two sources of supply may be present at the heater. Where pilot wires are installed separately from the heater final sub- circuit they should be protected, double insulated and carry their own integral earth continuity conductor.

    1. why not? Of course it depends where you are but in the UK, at 220v, the current is WELL below the limit for 1600w = under 7 amps. If USA at 110v then you would be pushing it and in that case I suggest not using the unit at 1600w.

Leave a Reply

Your email address will not be published. Required fields are marked *