Hi,
I have some sonoff with ESPEasy installed. While they’re working fine, i want to try Arendts’ Tasmota. Can I flash Tasmota bin firmware using inbuilt ESPEasy firmware update utility (web interface)?
Thanks
I think so… probably… just try. Whatever the tool does, it will not destroy the ESP (without warranty 
)
Update on the ITEAD recall of Sonoff Pow and Sonoff TH16.
I ordered two sonoff pow switches a few days before ITEAD published the worldwide recall. I contacted banggood custor service for a refund sending them pictures of my switches. The answer was kind of deceiving though. According to what ITEAD told to Banggood customer service, in fact, if the seal on Sonoff Pow switches is broken, the warranty is void. Moreover, the date on the seal does not necessarily indicate the production date. In practice, they will only refund damaged switches that have not been opened.
I opened my switch in order to program it with Arendst sonoff-tasmota firmware and I noticed that the amount of tin is identical to the images published on the ITEAD website (https://www.itead.cc/blog/sonoff-th16-and-pow-recall-notice). I therefore recommend to owners of these switches to be careful in their applications.
In my case I will try to monitor the temperature of the PCB on the bench.
It could be interesting to compare pictures of the PCBs for “potentially defective” and “non defective” switches. If you have an early sonoff pow switch (i.e. produced before decembre 2016) please post here a picture of the PCB (unless the OP judges that this is Off Topic). In any case, I think that these devices are not well designed for 16A. The case is too small. In fact I had some trouble connecting two 16A rated cables to the switches: the holes for holding the two cables are simply too small unless you remove the outside insulator.
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I was wondering about their safety, especially in absence of any electrical certification. With the Raspberry Pi Zero WiFi out at $10 now, I’m thinking that and a Crydom SSR might be a much better way to go, even over a Huzzah ESP8266
The missing certificate was bugging me too but hacking something together yourself will probably not be better nor cheaper… I’m a tinkerer in heart but it’s also nice to be able to buy a finished solution from stock for a reasonable price. To me these devices look well designed, I’d maybe not drive them with constant 16A though.
Of course not. Gogogo!
Someone published on youtube measurements with a thermal camera for a 10A load for different devices. (https://github.com/arendst/Sonoff-Tasmota/issues/221).
I would say that these temperatures are too high even for a 10A load. If the boards are enclosed in abox heat will accumulate and temperature will increase further.
In order to drive 3.5kW (i.e. 16A @230V), the minimum copper diameter is 1.5mm. (more details https://xtronics.com/wiki/Wire-Gauge_Ampacity.html)
I am not an electronic expert, but tin is 5-10 times more resistive than copper: I would naively expect that the tin required cross section increases accordingly!
EDITED (Updated with temperature measurements)
I measured the temperature under 10A load: after a few minutes, the tin gets as hot as 120 degrees!
I added some tin and i also soldered some copper, but temperature on that part of the PCB was always above 100 degrees.
I would say that these Sonoff Pows are not well suited for currents above 5A (or even less)!
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It is possible to set a Power limit for the switch. If the power exceed the threshold set by the command MaxPower for the amount of seconds set by MaxPowerHold then the device automatically switches itselff off.
It also issues a warning on the mqtt bus so that openhab can manage this exception.
A temperature reading would be obviously much better (which, by the way is available in my Fritz!Dect 200 reliable but much more expensive switches)
I have 4 of the standard Sonoff devices and 1 wall socket (UK 240 volt version). I was impressed by the quality of the build but not so happy about the solder enhanced copper tracks and the size of the relay. Luckily my applications are all low power but I made a mental note at the time not to use them with any high power devices.
I am an Electronics Engineer but have little experience with high current PCB design. However, you only have to compare the cable used in the UK to power 3KW appliances and these small copper tracks to realise that they are unsuitable for the specified 10 Amp current. A maximum of 3-4 amps maximum (at 240 volts) is my opinion.
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Hi, i use Sonoff POW and Sonoff-Tasmota firmware and connect to washing machine in stand by.
Set TelePeriod to 20 sec and look at Web page on Power value - it changes 0w -5w- 0w- 4w in 20 sec.
Power value sent to MQTT topic was sometimes 0w, sometimes 5w.
But i think Power value sending to topic must be AVG (0+5+0+4)/4=2.25w of power reading for TelePeriod for 20 sec.
Or i wrong?
Hello @martiniman, I didn’t quite get your question. Are you asking if the Tasmota firmware averages measurements? It does not. Evaluating measurements and processing them should be part of the next step. I can recommend Grafana to do so.
Hi @ThomDietrich, i mean when i set Teleperiod to 20 sec, i want to receive sum of power measurement in 20 sec period.
Is Tasmota firmware send to mqtt sum of measures in 20 sec, or only last second measurement?
Wattage is a timeless unit.
The measurements sent are samples from the moment of sending and can be seen as the current state of the consumer (similar to brightness, speed or temperature of something). If you are looking for consumption over time you need to integrate over the samples (sum over time).
If this is in fact what you are looking for Tasmota offers the “ENERGY” topic, which does this job for you and counts kWh:
e.g. tele/sonoff-xyz/ENERGY:
{"Time":"2017-03-27T21:02:28", "Yesterday":"0.029", "Today":"0.020", "Period":0, "Power":4, "Factor":"0.28", "Voltage":236, "Current":"0.068"}
I wonder if the concern here is to do with the granularity of the power measurement. It’s a cheap device, expecting to read power consumption in the 1000-2000W area. I would not expect it to be very good at instantaneous measuring say 3W consumption, some form of averaging over several samples will be needed, and even then may not be very accurate.
Hello Community I am trying to get my Sonoff itead Switch to work with openHAB.
Solved: My Old Problem
EDIT# I found out my topic is wrong it must be “cmnd/cmnd/sonoff-977686/POWER”
Now I can send ON or OFF command but it will not stay in this position, instead it switches itself back to the old state.
Someone knows how to fix this?
This is my current item
Switch LivingRoom_Light "Living Room Light" (ALL, Office_Workstation, Office_First_Floor) { mqtt=">[mosquitto:cmnd/cmnd/sonoff-977686/POWER:command:*:default], <[mosquitto:stat/cmnd/sonoff-977686/POWER:state:default]" }
#SOLVED
I changed the topic for the Sonoff Itead Switch to sonoff-977686 and now its working fine with the following Item
Switch LivingRoom_Light "Living Room Light" (ALL, Office_Workstation, Office_First_Floor) { mqtt=">[mosquitto:cmnd/sonoff-977686/POWER:command:*:default], <[mosquitto:stat/sonoff-977686/POWER:state:default]" }
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Hey everyone,
ATTENTION Version 5.0.0 specific information
just wanted to make you aware of the latest changes with Sonoff-Tasmota v5.0: https://github.com/arendst/Sonoff-Tasmota/releases/tag/v5.0.0
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What is the dimension of the PCB(not case) of the POW module? Need to fit inside my wall box:) I am planning to control my heating cables and with the POW module I can also see how much heating cost!
I’ve measured 89 x 45 (mm). Seems to be in line with the design: https://www.itead.cc/wiki/Sonoff_Pow
Did anyone have any luck with using the Sonoff SC with the Tasmota firmware? I had the sonoff S20 switches running in minutes, but now the SC will only send me default information over mqtt, no temp, or humidity etc…:
sensor/sonoffSC/INFO1 {"Module":"Sonoff SC", "Version":"5.1.0", "FallbackTopic":"DVES_F8B292", "GroupTopic":"sonoffs"}
sensor/sonoffSC/INFO2 {"WebserverMode":"Admin", "Hostname":"sonoffSC-4754", "IPaddress":"192.168.0.104"}
sensor/sonoffSC/INFO3 {"Started":"Software/System restart"}
sensor/sonoffSC/STATE {"Time":"2017-05-17T11:14:15", "Uptime":0, "Vcc":3.138, "Wifi":{"AP":1, "SSID":"Wifi", "RSSI":62, "APMac":"10:FE:ED:C8:AA:AA"}}Hey guys, this is probably me not understanding a core component of OpenHAB…
I have a basic sonoff device. If I toggle the switch in my sitemap then the physical light switches off and on as expected.
If I use the physical button on the device to turn it on/off then my sitemap is not updated, but if I just refresh my browser and the sitemap then the correct state of the switch is shown.
I don’t have this issue with some other switching devices so I’m not quite sure what it could be…
Any help would be appreciated. This is my item…
Switch Sonoff01 "Salt Lamp" <light> [ "Lighting" ] {mqtt="<[mosquitto:stat/sonoff01/POWER:state:default],>[mosquitto:cmnd/sonoff01/POWER:command:*:default]"}
Seems like another power cycle has done the job, it’s now working 