Hi Anthony
I do believe the switches I’ve personally used have no issue at all and will pass compliance certification. The only problem is that almost all our wiring to a wall switch is as you know a complete circuit as opposed to L+N to the switch and then L+N to the light. Broadlink switches do work but I would prefer Wifi Switches which for most people would require a complete rewire.
Hi Adrian
Thanks for the prompt reply and I am now looking at the Broadlink switches. It’s unclear to me if these MQTT out the box or do they need customer firmware like the Sonoff? If understand correctly the latest Sonoff switch firmware cannot be modified.
I see that Communica sells the Sonoff in SA and MQTT appears in the description http://www.communica.co.za/Catalog/Details/P0240254864 but I don’t know if this is only true with modified firmware.
I’m trying to avoid a solution that requires access to some proprietary cloud based server using a phone app and am currently looking at a Rasberry Pi / Node-Red / Mosquito MQTT setup but I’m not far from the bottom of the learning curve!
Assuming the Broadlink switched tick all my boxes, where did you get them?
Sorry - I realize that this is a bit off the topic of wall switches and more about IoT switches generally.
Hi
No need for custom firmware, HA integrates with them.
You need the RM Pro as the hub though.
I’ve been to Communica’s store. They are double the price of what you’d pay if you ship from AliExpress even. They are MQTT out of the box but you do need something like Tasmota running to integrate with HA.
I shipped them in from a direct contact in China.
So the slight issue with the Broadlink switches because they’re RF is that when you say tap the “on” button in HA, the command is sent to the RM Pro which is on the Wifi and then the RF Switch. On your phone for example it will show that the switch has in fact been turned on but it’s not an accurate representation of the state. Since RF is one way, there is no return signal from the switch to verify the signal has been received. Saying that, the 3 cases I’ve used them for clients I haven’t had an issue even through the floor, sometimes it’s just slower.
This can’t be the case. Otherwise, how does Aeotec do it with the Nano Switch?
Interesting. In my defense I am quoting the Inovelli engineer.
Thanks for the link to the Aeotec Nano because it looks like exactly what I need for one of my switch locations that has a single dual-gang switch in it.
But there are three different model Aeotec Nanos and I can’t find any difference between them except that the ZW140-A does power monitoring. Other than that the ZW139A is $55 and the ZW132-A is $70, but I can’t see any other difference.
Do you have one yourself?
I have an older version, called the Aeotec Micro. It’s quite a bit bigger than the Nano. Still, it works wonderfully and, along with my Innovelli switches, easily the best, and most predictable, ZWave device I have.
I also have GE Switches (eh), Linear/Nortek Dimmers (UGH!), Linear Motion Sensor (ok), Linear Door Sensors (good!), and one Zooz 4-in-1 Multi Sensor (UGH!).
It looks like a nice alternative, however neutral is needed. Bummer! 
I don’t see how a Z-Wave device can not require a neutral line, not counting battery-powered devices. There’s a processor and RF transceiver in the device that need power. If you are powering a light, why not put something like the Nano in the light fixture and wire the switch to the SW terminals of the Nano?
The real old Leviton zwave switches didn’t require neutral, and have been solid for me. I also bought some other old zwave switches, linear, which are not reliable for me.
I was looking at the nano dimmer, and it claims to not require a neutral either. But the nano switch did. But the dimmer needs enough load, or you have to add a load resistor.
Xiaomi Aqara wall switches do not requiere neutral. But don’t get me wrong, I was seriously considering Fibaro and this one is smaller, but if neutral is requieres I can assume I will be able to hide it behind the switch but rather in the junction box. It is convenient that the device is smaller, but it would have been extraordinary if I could have hidden it away behind the switch. Thanks for sharing.
Some devices do not require neutral, but operate by the leak current via the load or so. Sometimes this works, but it is not very reliable.
They work in exactly the same way as IR remote switches always have, they are in fact permanently on but only dribble enough current through to power themselves but not enough so you can see any light from the bulbs.
Wifi needs a lot more power than you can pull this trick off with so there aren’t any no neutral versions of them.
Hi Adrian,
apologies if it should be obvious, but why do we need separate power lines for the light and the Wifi switch?
(I’m a software engineer and have only rudimentary understanding of electrical engineering)
I am not understanding your question. If you are talking about the Nano Switch, the relay contacts are separate from the line powering the Nano. This way you can control low-voltage devices through the switch. In my case, the line voltage is jumpered to the relay common (in) and the light (out) is connected to the other contact of the relay.
The power line going to the switch with the nano switches is actually just a low voltage line. The actual switching is done in the nano device. The light switch is just a toggle in parallel with the zwave radio inside the nano switch.
Looking to add some smart wall switches to my HA setup but have some questions.
TIA
some houses (most in the UK) don’t have a neutral to the switch… like mine 
Lots of houses in the US don’t have neutral at the wall switch, especially if the house is a little older.
My house was built in the late 60’s, and most of my wall switches don’t have neutral.
They wire neutral to the light socket, but don’t bring it down to the switch. They just bring the hot wire to the switch box, with the “output” of the switch going to the socket.
This cuts down on the wiring that has to run through the house.
The Lutron caseta switches don’t require neutral, but they are fairly expensive. Supposed to be nice though.
Randy
Based on “today’s” electrical practices in most of the US, a standard (non 3-way switch) will have three wires running to it. A hot wire which carries power to the switch, a “Ground” which carries power to the load, and a “Neutral” (bare or green wire) that acts as a safety dump for power do get to ground in the event of a short circuit. The “Neutral” today by code has to be in every outlet, switch or light. The “Ground” isn’t always there in a 3-way switch situation. This is typically where you run into problems with smart switches today. Because the smart switch actually draws power at all times (to power the zwave radio), it acts as a load itself and has to have a “Ground” back to the circuit panel. That’s why it’s important to have the Ground at all switch boxes if you are putting in smart switches.
I think your definitions are not quite correct.
Ground is the term used for the safety wire that is connected to earth. This is a green wire.
Neutral is the return, which returns the current. This is a white wire. And while I do believe Neutral is required if building to current codes (note that I don’t actually know the codes as I’m not an electrician), I also believe many older houses (mine for example) do not have neutral wired to the switches. This is also the wire that most current smart switches need to work.
Hot is usually a black wire, and is what provides the voltage.
Randy
