Hi, I’m interested in replacing light switches and lights to zigbee smart switches and smart lights. I have the following questions that I would like to get clarified if possible.
I have brick walls and do not have neutral wires to the switches. This limits the options I may get from the market.
Since the switch sends power to the light, cutting the power off (or turning the switch off) will cut the power to the smart light and the light will be unavailable until the power is restored via the switch.
I am thinking about the following scenarios to mitigate this limitation by
jump the wires making sure the smart light is always getting power. Control will be done on the HA as a remote command. If the smart switch is capable of “decoupling mode” then this won’t be an issue and jumpering wires are not required.
If the switch is not supported in “decoupling mode” then wire the switch without any outputs to the smart light. The connection to the light is jumpered and will always get power and will be controlled via HA as a remote command. If the smart switch can be used as a remote control (no wires to the light bulb) this will help a lot by
A. Covering where the light switch is in the wall with nice looking smart wall switch
B. Having the same functionality as a physical switch (well, it's just a remote and no direct connection to the light bulb)
Since I’m fairly new to home automation (I’m located in Australia), could someone please be able to verify the above thoughts and let me know if a smart switch can be used without connecting to a light and using it as a remote so the light and switch can be used at the same time?
Also, any recommneded zigbee switches that’s certified to use in Australia without the need of neutral wire and external capacitors? I found MOES swiches (some variants) does not need neutral wires and external capasitors but they do not have Australian certifications
Do you have access to the roof or floor space where the switch wiring goes?
The reason I ask is because “no neutral” dimmers (there are no no-neutral zigbee switches I know of) are mostly awful. Way more reliable with a neutral, which your electrician can run in the roof or floor space and just use the existing switch wiring to the dimmer module. That’s how I had mine done. You will have to replace the switch mechanisms with push button mechanisms. Most switch plates have an option for these mechanisms.
Remove the smart light and replace it with a dimmable dumb one. If you need colour use the smart bulbs in lamps you can leave on.
Doing this ensures you can still manually control the lights from the switch plate if HA is down for some reason.
Hi Tom,
Thanks for the reply. Yes, I have access to the roof cavity and the electrician will be able to run a bypass capacitor to the first line if needed but that will draw some constant electricity and not sure about the reliability of the capacitor in a long run
The switches I would like to get as a replacement are the Zigbee glass plated touch switches. I’m hoping to use these as remote instead of directly controlling the light switch to achive
Switch will independently work with the smart light (both on Zigbee and controlled via HA)
If the switch is turned off manually, HA will trigger an event to turn the light off. However, this does not conflict with the scenes I may configure down the line (eg, turn on light when there’s a motion trigger) as the light still have electricity and can be controlled independently
Try before you buy, or at least before you put them everywhere. I had a glass plate dimmer and it drove me nuts. Had to hit it in just the right spot. I much prefer mechanical buttons.
What you want to do will work but as I said there are no “no neutral” zigbee switches that I know of. Only dimmers. You can use the existing switch wiring to supply power to the switch plate and permanently wire the light fitting on. There is some contention about this though. AS3000 wiring rules aren’t clear. Paraphrasing: “light circuits must be interruptible”. Does that mean you can use the circuit breaker? My electrician had no issue with it for my smart security IR bulbs.
The biggest issue you have is that if the automation is offline you can’t control the lights. This breaks the first rule of good automation design. The device must continue to work manually if the automation is not functioning.
Seriously, reconsider your approach. Many people have been down this read (me included) and have had to turn back and do it all again “properly”.
I would highly recommend the following products from Sonoff. Do not waste your time on Tuya or other products. Sonoff works well with Z2M and ZHA. Get Zigbee coordinators/hubs from https://smlight.tech, ideally PoE. Sonoff offers good coordinators as well but they are USB power only.
FYI Sonoff zigbee products communicate reliably with the coordinator and their reporting time can be customised. What most people miss about different products is how reliable the reporting algorithms within a device are, most products, especially Tuya, are junk (e.g. thermometers reporting every few hours or inconsistently).
I am not a Sonoff fanboy, and my advice is based on having tested a ton of products from different manufacturers.
Always bear in mind Zigbee is not easy to deploy (despite marketing) and it might take time to get a reliable working solution. It surely is orders of magnitude more fragile than WiFi.
Don’t forget that it’s possible to add devices like a Sonoff ZBMini inisde the light fixture itself, if the switch box has no neutral. This way the switch still works as people expect, but you can also control the light from HA.
I agree the most important consideration is that the switches need to operate as normal for family members and guests who maybe aren’t “into” automation as much as you are. Not to mention when HA or your automations fail. Smart bulbs are only effective if you can’t turn off the power to the bulb, which violates the first rule.
I have to disagree with the idea that Zigbee is hard to deploy. I’ve found Zigbee devices and ZHA to be totally plug-and-play. That’s really the only part of HA which doesn’t require any administrative overhead on my part. If I suspect some device may be too far from the rest of the mesh I just plug in a “smart plug” somewhere in between. They almost all work as repeaters, strengthening the mesh.
I’ve been shying away from off-the-shelf WiFi devices, mainly because they all want to use the vendor’s cloud, but also because they require some level of network administration. I’ve done that for a living, so it’s not difficult for me. It’s just another chore to maintain DHCP reservations and such. It’s also much more effort to “light up” a remote area with WiFi than it is to stick in a smart plug somewhere.
