Smart switch for "power through light"

I’ve been searching for a solution for a few of my circuits where the power from the breaker goes to the light before going to the switch. I think it’s clear that I can’t use a standard smart switch. Here’s one circuit that controls some outdoor lights. Note that there are 6 post lights all on the same line/switch.

Here’s my question: how do I get these onto a smart switch? if I connect the 3 black wires coming from the lights at my gang-box, all the lights turn on. All the white wires (neutral?) from the lights are already tied together. I’m open to suggestions …

  • I don’t need to keep these as 3-way switches. If there is a single pole application that works, I’m happy to tie off one of the boxes and skip that switch altogether.
  • I’ve seen others suggest using a relay at the fixture. How would this work, exactly? Especially when I have a fixture that is 6 different lights? (I have another circuit like this in my kitchen with recessed lights - same question on that one). I’m also concerned about space. I don’t think there’s room to cram another box into the post with the existing wiring.

I’m a beginner at wiring.

Is the problem with this that you don’t have a neutral in the switch boxes?

Tagging Michael @ritchierich

The neutral (white) wires from each of the lights are all tied off in the box. But the switches don’t want to work if power goes to the light first. I disconnected everything and tried to tie just the black and the white from one romex (I assume 1 light) to a smart switch. The switch gets power (LED comes on) but it doesn’t control the light at all.

When you have power to the light first, that puts the “primary” switch box in a non-neutral configuration. The primary switch box is the first box where the power shows up after being routed from the light.

So you can use an Inovelli dimmer which will install as a non-neutral at the primary box. If you want a switch as opposed to a dimmer, then the dimmer can be more or less configured to act like a switch.

The remaining boxes would require aux switches. As long as you can get a hot conductor and one traveler from the primary box, you should be good to go. There are typically 3-wire Romex run between the boxes, so that shouldn’t be an issue.

Also, depending on the lights, you may or may not need a bypass in one light box.

Replying to my own post b/c I think I do have something similar to this other places in my house, but this specific switch I was able to figure out. Basically, I have no idea where the wires come from / go to. The hot wire that I thought came from the post lights I was able to treat as the line. Another black cable that I thought went to the floods (because it was wired to the white from the flood secondary switch) I was able to use as the load, and voila - post lights on. I am now going to tap into the same line and the final black cable as the load for the floods. I’ll cap off the black wires leading to the satellite switches on both ends and just use the red and white.

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Thanks Bry. If I understand correctly, the Inovelli switch doesn’t require a neutral? Do you know if they are rated for LED? Most of the no-neutral switches I’ve seen are only for incandescent loads.

Yes, but you must use the dimmer, not the switch. Only the dimmer will function as a non-neutral.

There are rated for LEDs, but some LEDs work better than others. There is a compatibility chart on the support website. In some cases, you may need to install a bypass at the light. Inovelli says it’s if the load is <25 Watts, but I’ve seen users need the bypass where the load surpasses that.

https://inovelli.com/black-series-dimmer-switch-z-wave/