Keeping Existing Switches? (micro relays)

I agree, I’d hate to hard wire a bunch of z wave or zigbee switches and have them be obsolete in a few years. I just installed my ST hub last night and so far working great -hope I don’t jinx it. Only thing that sucks for me is as I remodeled the house over the last few yrs I installed legrand adorns switches and outlets over like 90% of the house and I like the way they look so guess for now I’ll be limiting the automation to things like outside lights which are pretty regular in their operation.

Today is not a good day for ST. In my experience when ST is working its about 95% (maybe a missed rule here and there). When they are in a bad state like the last couple days, its real bad. Hopefully they get everything stabilized today.

As for keeping the original looking switches check these out, they come in 1 and 2 switch model and are wired between the switch and the light (switch still works)

Thanks for the heads up. I’ll have to check them out later when I have more time. I assume they’re designed to fit in the box wired after the wall switch?

Thats the idea, but may be a tight fit. I have not used them personally but many people have.

Ya I’d have to check them out, a little nervous jamming something like that in the box. I guess you would have to leave the switch on to be able to use the automated functions and would have to have that unit switched on when you want to use the regular wall switch. Not sure if too many places where I need that but it’s good to know. It’d be better if legrand made some z wave or zigbee dimmers.

You don’t have to leave the switch on when you have a micorelay on the circuit. And you don’t use the switch independent of the relay. This switch just tells the relay what to do. The relay controls the current to the fixture.

You can put the relay inside the switchbox or anywhere else on the circuit where there’s a neutral wire. A lot of people put it in the light fixture if they don’t have a neutral wire at the switchbox.

thanks, I think I get it a bit more now. I imagine the switch sends power to the micro relay and then you can control it remotely from there? So if I wanted the ability to turn them on remotely I would have to leave the switch on. Legrand really should get with it and make some smart adorne switches and outlets though.

Aeotec is releasing the nano switches soonish — much better compatibility with modern LEDs, easier to fit behind the switch, better range, etc etc.


Not quite.

The micro relay is powered by the neutral wire on the circuit, so it’s always on no matter what position The switch is in.

Perhaps you were confused by discussion of smart bulbs. If you’re going to use smart bulbs, they get their power from the regular load line, so you have to keep the switch always on so that the bulbs have power even when the bulb looks off.

But that’s not how micro relays work. They are wired into the circuit in such a way that they get power even when the switch is off.

Ok thanks, the fog is starting to clear

This is not quite right – there is no power on the neutral wire. The relay is powered by the line (hot) wire, and needs the neutral to complete that circuit. The line goes to the relay instead of the switch, and both terminals of the switch are connected to a low-voltage input on the relay. (I’m sure @JDRoberts knows this and just misspoke/over-simplified, but wanted to make sure others aren’t led astray and try to get power from neutral alone)

Also note that the input of the dimmer module from the switch is just on/off. As far as I know, no relay product takes a dimmer input from a switch, just on/off. I’m not sure why that is, other than cost. You’d either need the relay to handle high voltage on the switch input, or have the relay powered separately from the line that it’s switching (so that line could be dimmed), and no-one seems to be making relays with such a design.

This is not quite right –
The aeon micro dimmers can be dimmed from the switch, not going to tell you it’s the most intuitive interface when used with a toggle, but it is supported and works just fine.
Works great with a momentary paddle switch.

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I use a number of the aeon switches. You can usually fit one behind a regular size switch/outlet in a standard single gang box. Fitting two behind two switches in a double box is usually too tight.

From the picture on the adorne web site, the switches look a bit larger than standard switches so the current aeon switches may not fit in the box and are probably better off putting them in the light fixture.

Aeotec does not have a good track record with releasing products “soon”. I have been waiting for the soon to be released Smart Film for more than 2 years now :slight_smile:

True, you can control the dimmer from a momentary switch. What I meant was you can’t use a dimmer switch input. So if you already have dimmers, they won’t work to control the brightness via the relay.

Right, but for the life of me I don’t understand why anyone would want to do this, and apparently the lack of a product like this means the manufactures also agree…
And in the end it just wouldn’t work anyway, think about it how it would (wouldn’t) work:
Take a dimmer with a slider, user moves the slider to 80% lights are at 80% now, then (via the in wall micro dimmer) sets the level to 20%, the lights are now at 20%, and the slider is at 80%…
There is no feed back path for the in wall micro to set the existing dimmers physical position, fail…

Good point for mechanical dimmers, I wasn’t thinking that through. There are electronic dimmers that just have momentary up/down paddles and could work (though I’d just replace those with proper zwave dimmers). I could also see using only the mechanical dimmer for dimming and the z-wave for only on/off, but that’s probably too niche.

the latter could be done without a special in wall device, using an in wall micro relay placed in series with the existing dimmer…

You’re right, I was thinking the micro switches wouldn’t work because they are powered by the same line they switch, but proper relays don’t have that limitation.

V[quote=“mishakim, post:11, topic:42540, full:true”]


I appreciate the assumption that I do know what I’m talking about and just misspoke, and maybe I’m just wrong, but my understanding is that the Aeotec micro dimmer does, like most of the zwave wall switches, get its power for the radio from the neutral.

Otherwise you’d be able to install it into a switch box without a neutral (replacing the existing switch wiring) and just rely on the neutral at the light fixture to complete the circuit.

Regardless of whether I’m right or wrong about the relay, though, in the US there is definitely power on the neutral wire. As I said, that’s how most zwave wall switches work.

But again, I could just be wrong. @Navat604 might want to say more.

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Jd’s right of cource, the neutral is the return for the hot, without a neutral there can be no current flowing…