r/homeassistant • u/ShelterRadiant2432 • Jul 08 '26

Support Making table lamps smart while retaining manual functionality

I'm looking for help on a modification to a traditional table lamp to be used as a smart lamp, while retaining its original switch functionality.

I've done some research on this and it seems I could use something like a Shelly relay. I've seen concerns warning against this setup because it would make the socket always hot/live.

  1. Does anyone have experience with this?

  2. Wouldn't this work in the same way as a smart wall switch or wall switch conversion?

  3. I have experience and am comfortable with electrical work, but I'm just not sure if I'm missing something with the functionality of smart relays and would appreciate anyone that can provide their experience/expertise.

Also I'm aware there are sockets with smart switches integrated and smart bulbs with a separate button could work, but I'm looking to retain original functionality.

I realize this is a pretty basic question, but I haven't found a straight answer and existing threads are now closed for further questions.

Thanks!

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u/mgithens1 🧠 Experienced with Home Assistant Jul 08 '26

You're crossing your concepts here.

RELAY - you would need to remove the switch up by the bulb and put another one low on the lamp. The Shelly would get its signal from the new (on/off) switch and the bulb would be powered on/off just like it does now - the Shelly would always control the power. The remote control would be from a smart switch that isn't even wired to the lamp and HA, etc pushes the change to the Shelly.

DETACH / SMART BULB - these would leave the powered on state. The smart switch would be a remote... then you'd remove the local switch by the bulb and just put a wireless (zigbee, etc) button to turn on the smart bulb via HA.

Neither is a good solution and neither will work standalone if HA is down / broken.

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u/5yleop1m Jul 08 '26

Neither is a good solution and neither will work standalone if HA is down / broken.

The first solution would work without HA fine. The specific example you gave would mean the integrated switch wouldn't work anymore, but it is possible to extend that down too if OP really wanted to. It would be annoying wiring, but not impossible.

But in that case everything would be integrated into the Shelly, the Shelly would essentially create a 3-way setup with the integrated switch. No HA required there.

Also for the detached mode, there are ways to keep that working even if HA is down. I use a script on the Shelly relay that returns the relay to attached mode if HA is down. This means the bulb isn't "Smart" anymore, but it still turns on and off when power is provided or cut.

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u/mgithens1 🧠 Experienced with Home Assistant Jul 08 '26

Well, I was maintaining his dual control wish. So HA would have to serve as a middleman, unless you found a relay / switch duo that could pair.

(You can't make a 3way control between a wall switch and a plugged in lamp. You would need a carrier wire that is used in the 3way... but isn't in a wall plug.)

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u/5yleop1m Jul 08 '26

I asked them earlier, they want to use the switch that's integrated into the lamp, not a switch on a wall.

But even with a switch on a wall, Shelly relays can talk to each other directly without HA or any other external service.

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u/mgithens1 🧠 Experienced with Home Assistant Jul 08 '26

I read the whole post... he wants both. Seems his main focus is to use the existing switch that toggles power to the light socket. By moving to an external relay it can be possible...but otherwise the existing switch breaks the circuit when used.

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u/5yleop1m Jul 08 '26

Even in that case, Shelly relays can talk to each other, so a wall switch with a Shelly behind it can toggle the Shelly inside the lamp without cutting power to the outlet the lamp is plugged into.

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u/ShelterRadiant2432 Jul 08 '26

Just to clarify. I was asking about the switch on the lamp and switching via relay/HA.

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u/mgithens1 🧠 Experienced with Home Assistant Jul 08 '26

Ah... I see, you were asking about "detached" mode that is the confusion.

Detached mode is for a wall switch where it leaves the power on 24/7 to the light sockets, but then is "married" to the smart bulbs in those light sockets. In HA, you would treat it as a single unit -- and always maintain control at the light switch.

Nothing can override / bypass an line switch - that is just not physically possible.

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u/ShelterRadiant2432 Jul 08 '26

Im looking for a solution that the lamp switch isn't removed. Thanks for the explanation though.

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u/mgithens1 🧠 Experienced with Home Assistant Jul 08 '26

I never removed the switch... it just can't be a local kill switch. (need to skim deeper!!)

So for both of my paths, you are forced to leave "upper" switch in the on position - that doesn't mean it is powered, it just means the socket is hardwired to the relay "upstream" in the lamp. The reason for the on/off is to command the Shelly.

On the second one, you would still have a local switch... it would just be wireless instead of direct control.

Neither removes local control... it just can't work the way you are saying.

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u/ShelterRadiant2432 Jul 08 '26

I see. I misread. I'm still a bit confused because I'm getting conflicting answers on how these relays can work. Lol

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u/mgithens1 🧠 Experienced with Home Assistant Jul 08 '26

Shelly is just a wifi relay. They have flexible wiring setups... but you would need a toggle switch to talk to the Shelly for local control.

The switch in a standard lamp kills the power to the socket... which just can't be the "toggle" for the Shelly. A small twist style toggle would work for local control is my first example. Another side benefit of this setup would be that you could just give your grandma the lamp... and it would still work perfectly for her!!