For Tuya, there are many different models from many different manufacturers.
Some of them work well. Some do not. Sometimes the devices will have the same model number but different firmware and one will work well and one will not.
Tuya creates the basic device but then the individual brands put their name on it and make some changes.
So the one you get might work or might not.
If by āsmart lightsā you mean āsmart bulbs,ā then yes.
The exception is the Sengled brand which were specifically made to work with dumb switches.
They are not Zigbee repeaters, so turning one off at the switch does not hurt your network.
They were engineered to tolerate inrush current better than most smart bulbs do.
However: if you turn a Sengled bulb off with a dumb switch, you must turn it on again with the dumb switch before it will work with home automation again. You cannot turn it off with a dumb switch and then turn it on with the app or voice or a routine. Some people are OK with that, some are not.
Also note that the Sengled Bluetooth models do not work with SmartThings. The Sengled Element models, which are Zigbee, do work with SmartThings. The product description for the Zigbee models may say that you need their gateway, but you do not: you will use a smartthings hub instead.
But for all the other brands of smart bulbs, you must get a smart switch which is specifically designed NOT to cut current to the bulb, but instead communicate by radio. Or just leave the dumb switch on all the time.
Then Iāll by the ones Mariano_Colmenarejo recommend to be sure they work.
Smart bulbs would not be as useful as it should for my family (even the Sengled ones), so Iāll go for the aeotec dimmer since is the simplest solution.
Thank you all!!
That specific model does require a neutral wire, though. 
Hi @Bralok
Regarding Girier module you posted
Please be aware that it does not notifies the hub when you use the physical (dumb) switch, attached to it. That means, the hub would need periodically poll the module state in order to show the correct position. It is OK for a couple of switches, but it would create a substantial load on Zigbee network for large number of devices.
And it also requires neutral wire
Thanks for the hint, Mariano_Colmenajero. 2 questions here:
@JDRoberts, my light installation has neutral but not ground. Since Mariano_Colmenarejo also pointed the neutral requirement Iām curious. How the electricity āreturnsā if an installation has no neutral wire?
@ygerlovin, @Mariano_Colmenarejo , can this device work with dumb switch or dumb dimmer is required?
Thanks
I know how it works for US wiring. I donāt know if itās different for European wiring.
In US wiring, The switch is just a cut in the circuit that runs from the mains power to the light fitting. It opens the cut and it closes the cut.
If the neutral wire is not at the switchbox, itās somewhere else on that same circuit, usually at the light fitting. So the current returns from that point.
In the case of a dimmer, the design allows it to change the amount of current which is let through to the light fitting. More current means a brighter lamp. But otherwise itās the same idea.
For a smart device, the radio inside that device, whether it is a smart bulb or a module, has to have power all the time or it canāt hear the next network command.
If the smart device is an on/off relay, then typically it will get its power for the radio from the neutral wire.
If the smart device is a dimmer, it is possible with some models to borrow a tiny bit of power from the hot line, so that there isnāt enough power to make the lamp light up, but there is still enough power for the radio. But the device has to be designed to do that. And not all of them are.
Again, though, Iām not an electrician, and I donāt know if itās different in other countries.
It is hard to tell without knowing the exact model and even then there could be firmware differences.
However, Moes devices are not known to have such problem. They have another issue though, some devices have a firmware that implements Tuya specific protocol, while others implements a standard (or close to it).
This particular device looks like ms-104, which should be OK, but I would suggest to order only one and see wether it works OK. If it does, then order more from the same seller
All modern electrical installations have Ground, Neutral and Phase (1, 2 or 3 phases). Normally in a house they are 1 Phase, Neutral and Ground (monophasic). In Spain 220V of alternating current.
We could say that the neutral is grounded in the power plant generator.
If you measure with a multimeter the voltage between the phase and the neutral and the phase and the ground is exactly the same.
If these measurements are different, it may be an indication that your grounding installation is faulty and you could lose protection against electrical shunts.
Grounding wire is for user safety.
If an electrical appliance, washer,ā¦ has a shunt from the phase to its chassis, the current that must flow from the phase to the neutral and vice versa, since it is alternating current, return in part to the wired ground and the differential switch in the panel of the the installation will detect that the input current (L) differs from the return current (N) by more than 30 mA and will trip the general switch of the installation.
If You do not have a ground wire, the current derived from the chassis does not flow to ground wire and the differential switch will not detect a difference in input and return current until you touch the appliance with your hand and the derived current passes through your body. At that moment, the differential switch will save your life when more than 30 mA pass through your body.
The switches cut and connect the phase that goes to the bulb and the neutral is always present on the other terminal of the bulb.
If the Neutral is not in the switch box to power the device, you can look for it in the junction box that is usually higher on the way to the bulb.
When you want to use a device without Neutral, what happens is that the device changes the mechanical relay for an electronic switch with an adjustable high impedance (triac or thyristor) and uses the neutral that comes through the resistance of the bulb to feed the electronic circuits of the device.
These dimmers require that the bulbs be of the incandescent type, allogen ā¦ so that the neutral can reach the device.
If you are going to use led type bulbs, which have an electronic circuit, it must be of the dimmable type and a capacitor may be necessary in parallel with the bulb so that part of the neutral current can pass through the capacitor to the device. There are certificates like this one from fibaro, but if you search on the internet you will still find cheaper.
Than you all for such detailed explanations.
@Mariano_Colmenarejo , I meant that I donāt have ground wire in the switch box but I do have it in the junction box. Regarding firmware comment from ygerlovin, the link you provided is for the same seller you bought your devices? Otherwise, I guess I should buy jut one and try.
@ygerlovin , this one looks like the Moes MS-105Z dimmer, right?
And what about this?
Would they work with dumb switches?
Regards.
Yes, i bougt in this AliExpress Moes official store.
You have in Amazon too, to 22.99ā¬ switch and 26.99ā¬ dimmer, if you need to try prior to purchase more quantity
MOES Interruptor Tuya ZigBee 3.0 Inteligente conmutador Inalambrico MĆ³dulo Alexa Control Remoto y Rele RF433 para Interruptores de 1 Gang y 1/2 Way, compatible con la app Smart Life Tuya Google Home https://www.amazon.es/dp/B08KZK69NR/ref=cm_sw_r_apan_glt_i_PFVQV9DJ2S2J4F6RMRHF
Device in Amazon is ZM-105-MS
Yes, the one gang dimmer looks like MS-105Z.
Please note, my driver does not support 2 gang version
Great, Iāll buy those then.
Thanks, I just need 1 gang version.
