Sonoff TRVZB review + setup + NO-BATTERY Hack / battery eliminator adapter

[@byfunkyoid2917]

This is the best video. Thanks so much!

[@mrflibble5311]

I didn't know they existed . Could be very useful . Good hack , I for one would forget about the batteries and leave them in all summer leaking away.

[@NicksStuff]

Netatmo make some too that work in conjunction with their thermostat

[@cornebistouille]

i set up my entire home with those heads, they are very good for the price, and now i can monitor all my heaters. though i have exactly the same zigbee hub, i will upgrade soon with a home assistant setup, the e we app and cast are too basic and need a paiement upgrade to offer more possibilities... and i have also privacy concerns about all those connectivity apps...

[@okkiesmaster7820]

Sir, can i als do this with a potato?

[@MyProjectBoxChannel]

I don't know what you mean🤔? But you are welcome to do whatever you want, with your potatoes 🥔. Be my guest👍😜.

[@angeloamatruda8397]

Like it... Definitely looks brighter with the battery hack ensuring a very smooth powerful consistent operation.

[@NicksStuff]

Have you measured the current of the device? I often wonder if the batteries could be recharged by a Peltier module. I don't know why but I find this idea very elegant for a radiator. Otherwise, a small solar panel should be able to do it without requiring a nearby mains plug

[@MyProjectBoxChannel]

That is such a great idea 💡. The TRVZB is definitely a "low power" device because it is zigbee😉. The actuator motor is probably the worst culprit, but it's not in constant use. The peltier energy harvesting, could work for a simple "trickle charger" for the Nickel-metal hydride batteries. The cold side off the peltier might need a "large" heatsink. I think a prototype might look a little frankenstein, but it could prove the concept. A small 6v PV panel could also be affective to trickle charge the battery. You don't need complicated charging circuitry for Nickel-metal hydride cells.

[@BSOE3058]

Idea: instead of messing with batteries I would use 2 flat-head metal pins and pieces of hotglue stick

[@MyProjectBoxChannel]

I did actually try two pieces of hot melt glue sticks 😂. They get a bit flexible with the heat next to the radiator. But it was definitely my first thought😉. It probably would be okay. I just prefer something stiff and rigid. You could use any thing that has a similar diameter.

[@danielf2025]

Considering how little power the TRVs use, I do wonder if a peltier element attached the radiator would produce enough current to keep them charged...

[@MyProjectBoxChannel]

That would be a interesting experiment to try🤔😉. You might need to stack several in series to get the voltage required. Or maybe bigclive's "joule thief" circuit, to boost the voltage.🤔

[@husseinsharafaddin1851]

Thanks for sharing. This is a good idea. I have a question regarding the water flow in the radiator. Usually these valves are installed in the in/hot pipe and the in/hot pipe shall be installed at the top of the radiator. In ur case the valve is installed at the bottom. So my question is: Is the in/hot water pipe the one with the valve at the bottom? Where is the out/cold pipe installed? Do u face any heating power lost? I have a situation where the in/hot pipe is at the bottom and the out/cold pipe at the top. With this setup the radiator doesnt get warm correctly. Thanks

[@emmanouli]

Good morning from Greece. The use from WiFi for this thermostat, is available only by a Zigbee Hub or I can control it only with the thermostat itself? Thank you for your response

[@MyProjectBoxChannel]

Yes, you do require a zigbee hub. Zigbee is ultra low power, so it's often used for battery operated devices. WiFi is very power hungry, and not easy to power from batteries.

[@NicksStuff]

I believe a brand new Alkaline battery can deliver up to 1.65V, so 4.95V for all three. I wouldn't bother with the diode and resistor...

[@MyProjectBoxChannel]

I did think of not putting the diode, and 5 volt would probably be just fine. I just wanted the keep the voltage closer to 3 x 1.5v , but I found some cheaper USB chargers could be as high as 5.5 volt. So The diode could help with the higher voltage.

[@UKenGB]

Yes, I tried that (see above) and it worked with one USB adapter, but 2 other adapters failed. I suspect that the TRV tries to take too much current for some adapters and they fail with a "POP!". Maybe when first powered up, the TRV attempts to power the motor which for some USB adapters draws too much current. Annoyingly that last attempt seems to have damaged the TRV which no longer powers up, even with the adapter that previously worked. Did the USB adapter failing send a voltage spike to the TRV causing that to fail? So I'm thinking the diode may be useful as a current/voltage limiting device and help stop blowing up the adapters and protect the TRV. However I have to trust it will work and not damage another TRV.

[@NicksStuff]

@@UKenGB If it's when first powered up, maybe an NTC thermistor would be indicated

[@UKenGB]

​@@NicksStuff Yes, it's when switched on. Well within a second or so. Why do you think the thermistor would help? Not sure I understand why.

[@NicksStuff]

@@UKenGB NTC in series help to reduce in-rush current (if there is a power supply with capacitors, for instance). Why? Because when cold, they offer a high resistance (so, low current), gently heat up and reduce their resistance

[@Simpleboneguy]

Brilliant Sir. I'm gonna try it.

[@UKenGB]

This is EXACTLy what I'm planning, so good to see it works. However, would be really great to know if it would work without any voltage reduction. Any such 3 battery device has to be able to accommodate at least 4.8V and I seriously doubt 5V would cause any problems whatsoever. Any chance you could test this and report back here?

[@MyProjectBoxChannel]

I'm 99.9% convinced it will work fine directly on 5V. I would just make sure that my 5v power supply is outputting no more than 5V. Some cheaper ones have a big tolerance.

[@UKenGB]

@@MyProjectBoxChannel Why don't you try it? Go on. You know you want to. 😄

[@UKenGB]

@@MyProjectBoxChannel I finally got around to trying this. I soldered the + and - wires from a USB cable directly to those battery terminals on the TRV. Easy to do and neat. Connected to a (unbranded) USB adapter which promptly went PHUT! Supposedly a 2.0A PSU, but now a 0A piece of plastic. Tried an early Apple 2.0A USB adapter (from iPad) and the TRV powered up and after normal setup procedure it was visible and working in Home Assistant and has been for the last few days without any signs of warming up (rad was mostly off). I wanted to see if Apple's 1A adapter could power it so tried one, but that went PHUT! So I connected it back to the 2.0A adapter with which it had been working. Unfortunately the TRV is now non functional. I have 5V at the connections, but it's dead. 😩 So somehow when the Apple 1.0A adapter failed, it also took out the Sonoff TRV which is not only annoying, but a complete puzzle. How did that happen. Seems likely the TRV is trying to draw more current than some adapters can supply and when they have no overcurrent protection, they fail, but how would that break the TRV? The big question now is whether running from a suitable 2A adapter can be relied on. Oh and how to fix a blown TRV.🤔

[@lesotter7241]

Hi - maybe I'm being thick, but why doesn't the tin foil short out on the zinc casing making both ends the same voltage potential? is the zinc tube lined with plastic ?

[@MyProjectBoxChannel]

Yes you are correct each tube is completely sorted to both sides😉. But it doesn't matter! Because we are only using two dummy cells, and the middle cell is not used. So we only care about making a connection to the main positive and main negative spring terminals, on the Sonoff trv. If you tried to install the middle battery/Cell , it would be a problem.

[@diver_frank]

The diode is a 1N4007 and the resistor is ?

[@MyProjectBoxChannel]

I used a 4.7K resistor but it's not critical, 1k to 10k should be fine. The diode could be a 1N4007 or similar type.

Hello. My fried. Brasil

[@markusheitmann]

Can you do a video of this battery hack on a "zemismart roller blinds"?

[@boembajee]

Just put 5V on the first + and last - lead, no need to mimmic batteries I imagine?

[@MyProjectBoxChannel]

Yes 5v is probably fine, and inline with in the aloud voltage tolerance of the device. I did however notice that some cheaper USB chargers, could have a output voltage as high as 5.6v, so dropping 0.6 volt acrossa diode is not bad thing. You could just solder the USB cable directly to the battery terminals, but the dummy battery's makes it easily reversible.

[@bartn4495]

Rinsing the battery out under your drain, drained my ecological hope for this planet 😢

[@MyProjectBoxChannel]

The black stuff I was rinsing out of the zinc carbon batteries, is manganese dioxide! It's used in water purification, and it's mostly benign to the environment. It's a naturally occurring mineral. Breathing it in as a fine powder is not great for your lungs (like most fine powders). It is one of the least toxic battery chemistries. It was the zinc casing I was after, which is probably the worst thing in the battery. If it was any other type of battery, like lead-acid for example, I would never do this. It would simply be too toxic to the environment.

[@bartn4495]

Glad to read your sincere considerations@@MyProjectBoxChannel. Might be good to mention or annotate such info in the video.

[@MyProjectBoxChannel]

​@@bartn4495I think I mentioned it's fairly benign. But you are right I should have explained it in detail

[@eugeneeman7710]

Interestin accent. Where are you from?

[@MyProjectBoxChannel]

I'm originally from South Africa, but haven't lived there for 23 years.

[@halimhussein]

hi, i came across your you tube because i am looking solution for my problem. i have more less have an idea how to solve it but i am not electronically savy, so i not able to build up the circuit it involved 3 phase current, sonoff 3 gang switch, no neutral switch, because my present 3 gang switch powered by two live sources. i want to replace it with sonoff 3 gang switch but the problem is sonoff switch is design using one live source.

[@MyProjectBoxChannel]

OK 👍. But I need a bit more information. What voltage 3-phase do you have?(the voltage between two phases) Do you want to switch all of the 3-phases? Or just 2, and do you need to power the Sonoff from the same 2-phases? Also you mentioned you have 3-phase but no neutral connection right? It is possible to use 2 phases, to provide power to the sonoff, as long as the voltage is within the right supply voltage range, for the Sonoff. So you use one phase as the L, and a different phase as the "N" in.

[@halimhussein]

@@MyProjectBoxChannel both power source are 240v. the original 3 gang switch configuration were 2 of the switches powered by L1 and one powered by L2. i have 3 gang mechanical switch that works on ewelink. but this switch do not have neutral connection. similar to my existing house wiring do not have neutral line. so i am thinking to use L1 and out3 to trigger SSR to act as switch or opto-coupler (possible?) to connect L2 and OutL2. but i do not know how to power up SSR (or opto coupler) as my wiring circuit do not have N Line.

[@MyProjectBoxChannel]

​​@@halimhusseinI'm a bit surprised how two different phases are being used on a 3gang switch, in the same back box🤔🤨. So I guess L3 is up by the light fixtures(like we would have the neutral) and L2 and L1 are being used to feed the light switches? I'm trying to get my head around it🤔. So It should be possible to power/feed all 3 switches from L1( as long as the light fixtures up by the ceiling, are feed by L3 as the return). You could test this with your old light switch, and see if it works. You will have L2 free. Then you can use L2 as the N-in for your sonoff switch. L1 can be L-in. The 3 outputs can switch the L1 feeds back up to the lights. ( I don't know what model 3-gang smart switch you have?) Let me know what you think. It's important to know what phases are up by the light fixtures. If it's L3 for all the lights, the it should work.😉👍

[@halimhussein]

this is the fault of my renovation contractor. i didnt know they did that, it has caused alot of tripping when i replaced with smart switch, only then i realise what they have done.😮 . i do not know how many of my house switches are on 2 live source. of course the simplest solution is to hack my wall and place another single switch to take of another live line. i saw one of your video using optocoupler as switch, i might get 3gang switch with neutral line if that can make it work. anyway i ll try your suggestion

[@halimhussein]

this switches to light up light fixtures