Diagnosing 3-way non-neutral aux setup


I’m trying to diagnose why my 3-way Inovelli Blue (fimrware ) v2.14+ Aux wiring setup isn’t cooperating. I’m in a 1920s US home with pretty old wiring, but in decent enough condition.

I have 2 conductors feeding power to a light, then to switch 1 (Inovelli Blue). There are three conductors that go direct from switch 1 to switch 2 (Inovelli Aux) - verified continuity with a multimeter. I have the power feeding to load and line on the Blue, then a line from the line on the Blue to Neutral on the Aux and a conductor from the traveller on the Blue to the traveller on the Aux. Switch has been tested in both multiway toggle and multiway aux mode.

Current behavior is that the switch power up fine, but the light is always on at partial brightness. Switch presses on both the Blue and the Aux do nothing. Measured voltage across the line and load is at 60V (!).

It’s possible my ground is messed up (the 60V). It’s also possible, but unlikely, that power goes from SW1 to the light to SW2, but again, I’m pretty sure I’ve traced this correctly (with a circuit tracer).

And advice on this would be greatly appreciated! My next step is to get an electrician to verify my trace work.

So it sounds as if you have a switch loop. In other words, a hot and neutral to the light and then just two conductors (excluding ground) going from the light to the switch.

Did you test to determine which of those is hot? You can use a meter to test between each conductor and ground (if you have one) or use a non-contact tester on the conductors individually. Want to see how you determined which conductor to connect to the Line terminal and which to connect to the Load terminal.

At the switch? That’s not a valid measurement. You are measuring between a hot and the other side of the hot after it goes through the meter . . .

I’ll have to recheck this when daylight is back out, but I’m pretty confident it is breaker → light (2 conductor) → switch 1 (3 conductor) → switch 2. I was testing each conductor via both multi-meter continuity (against ground) and via a Fluke circuit tracer. If I directly connect the two conductors coming into sw1 together, the light turns on at full brightness. I certainly could have made a mistake though – I’m pretty new to this. I’ll report back!

No, your description of the flow is likely correct. When you have that, it’s called a switch loop. When you touched the two wires together, you simulated a switch.

But in this configuration, for the two conductors in the switch box, one of them will be hot and the other will not. The 2nd wire returns the switched hot to the light

Before you wire the switch, you have to know which of those two conductors is hot, and that conductor goes to the Line terminal. I’m not sure you tested to determine which of the two was hot before you wired the switch. Let’s get that fixed first, then worry about the rest of it.

Sorry for ghosting on this thread. The past week was a bit crazy for me.

Going back to basics, I confirm on the 2 conductor coming into this box (and signal tested as going to the light), I can multimeter test to confirm one is live. When shorted together, the light activates at full brightness. Pretty sure this is the right pair. :smile:

When connecting the hot wire to line on my switch and the return (to light) wire to load, the switch boots and appears to operate normally, but the light (a combination of 2 LEDs and a halogen) lights dimly. No mode set on the switch (dumb switch, aux, etc.) ever allow the light to be switched off, though the switch seems to respond normally to inputs.

This doesn’t completely surprise me as the switch has to pass enough current to run itself. Not being able to go to full brightness (or something approaching it) seems odd though.

I think you lose a bit of max brightness in a non-neutral config, but not to the point of being dim.

I’d check the max brightness value to make sure you are not limiting the max.

I’d also try one bulb type or the other temporarily just to make sure the mix isn’t affecting this.