Smart Bulbs (that are ZB routers) with Smart Relay Modules (that are ZB end devices)

I have recently had an electrician install some zigbee relay modules on some of my switches - but one of them goes to a series of smart bulbs. I was hoping to have the bulbs bypass the switch, however the specific relay I got (sonoff zbmini2) doesn’t use a neutral wire, so it needs to be actually hooked up to the lightbulb.

Well, I thought I could make this work via an automation - when the switch gets switched off, I switch it back on and toggle the lights! However, this was working incredibly inconsistently, and getting weird behavior where after I’ve flicked it a couple of times to test and then walk off, it would turn off by itself several seconds later. I fiddled with the config, and length of the delays, but it seriously just wasn’t working.

Today while at work I realized a potential issue - they are ZB end devices, and their nearest routers would be the lightbulbs themselves. Since those would be turned off when the switch turns off, it would disconnect the switch and prevent it from receiving the message to turn back on. Looking on here it seems the “solution” is to just never turn off ZB routers. I’m using ZHA so I don’t believe I can just prevent the bulbs from being routers, and honestly I’m not a huge fan of this hacky solution to begin with.

So my question is, how do I wire a relay so that the switch gets power and can communicate when it’s toggled, but the bulbs just always receive power? If necessary I can buy new relays, but I’d rather avoid it if necessary. (the zbmini 1 might be a contender here, being a router and using a neutral wire, although the gang box is already incredibly cramped with the smaller zbmini 2)

Initially I was wondering if I could just connect the zbmini2 so that it tries to “power” the neutral wire instead, but I’m pretty sure that would just short circuit whenever the switch is on the “on” state.

I think if I end up going with the zbmini 1s, I could just not connect the lightbulb (that is, just leave L out disconnected)? I think it’d still operate, and then I could wire the lightbulb to always be on.

If I’m reading that correctly, the smart switch module is still controlling whether there is power to the smart bulbs or not ?

So the smart bulbs can have their power withdrawn ?

As you are probably aware, smart bulbs are designed to be powered up permanently, and the on/off state of the bulb controlled via (in this case) Home Assistant.

Whenever the bulb is losing power, it can take some time to reconnect to the network. In my experience, this is usually just a few seconds, but your mileage might vary, and its certainly not ideal, and it all also forces other devices currently routing through the bulb to re-route… and for some devices like Aqara’s, which don’t do this… they’ll go offline.

As for how to wire the switch, that depends on your internal wiring setup. If the bulbs are on the same wiring circuit for both the smart and dumb bulbs, I think the answer is… you can’t, without re-wiring, assuming your wiring looks something like:

Switch – smart bulb – dumb bulb – dumb bulb – smart bulb. (The order doesnt matter)

I dont think its relevant if there is a neutral wire at the switch or not.

In the UK, this is a typical ‘ring’ circuit, and the last bulb loops back around to the switch. But again, depending on how your house is wired, and where you live, this might be different.

Yeah, that’s the current setup, and I’ve noticed the issues it has wrought! Fortunately all the bulbs on that circuit are smart, so I really just want to have them all always powered (bypassing the switch entirely), it’s just that I’m not sure how to wire the smart relay such that it can still transmit the toggled event to HA. These are the wiring diagrams they gave me, and the understanding I’m getting is the bulb is required for the relay to work:

Is there more than one switch in your house controlling the lights we’re talking about ?

If its a single switch, its pretty simple. The two wires that would have gone through the top and bottom of the original switch unit just need to be wired together. 2 way is more complicated…

The other option, given that all the bulbs are smart, is rather than have a switch module wired into the house, is to put the original dumb switch back and cover it over with a wireless switch like so:

I do have some bulbs with 2 switches, and some even with 3, but I haven’t messed with those (yet). The ones with the issue at the moment just have the one physical switch.

I understand that I’d need to wire it so the bulbs always get power, the issue is I want the switch to still tell the relay to send an event to HA so I can toggle the lights. I don’t just want a dummy switch that doesn’t do anything.

Also, I appreciate the link to the adapter but I don’t think that’ll work for me in this case. The switch in question is part of a 2 gang box, and the other switch is to the fans, which are not smart.