Wattage Minimums for Non-Neutral Installation w/o Bypass


I have a circuit with power coming into the fixture first and no neutral in the box. The light fixture has 2 60W sockets for bulbs. I had installed an Inovelli Red dimmer in non-neutral mode with no problem with 1 60W incadescent bulb and 1 60W equivalent LED bulb as a holdover until I received higher lumens LED bulbs (the light created was insufficient).

I specifically made sure the actual wattage output of these LED bulbs was above the 25W minimum. I bought LED bulbs that are 100W equivalent and have an actual wattage of 14.5W. My understanding was that this would work because 14.5 x 2 > 25. However, I just put the bulbs in and can confirm I lose power to the switch as a result. If I replace 1 with the incandescent it works fine.

For reference, these are the bulbs:


Please advise if my math is wrong and why I need a bypass.


It’s not a perfect science, particularly with LEDs. I don’t know whether or not your two LEDs combined are pulling more than 25W. I also don’t know if even though 25W is the published standard if that’s truly accurate. There have been cases where users have needed bypasses to resolve issues on neutral installations.

So it sounds like you need a bypass because it’s not working without one. I’m guessing you’re asking because you did the math and it’s not working per your calculation. Unfortunately, it’s not that simple, particularly when LEDs are the load.

Thanks Bry. I was expecting this to work because the information from Inovelli says: " You will need to install a bypass if your total load is below 25W." It was on this basis that I purchased this particular switch for this room with a particular set of bulbs with a disclosed value higher than 25.

If this is not an accurate statement and it’s more “it might work, depending on the bulb”, I suggest that be communicated to avoid a similar situation for someone else.

For my situation, can someone provide a bit more information on how I would install the bypass. I want to gauge whether it’s worth buying this device on Amazon and continuing to use these bulbs or to experiment with higher wattage LED bulbs (I would have to give up RGBW for this as this is the highest wattage RGBW bulb in this line). Is the scope of work removing the fixture, and inserting this device between the romex endpoint and the fixture?


It goes in parallel with the light connections in the light box. One to the hot, one to the neutral. Tuck it up in the box.

@Eric_Inovelli I have an idea for a product: a screw-in bypass. A thin adapter which screws in between the socket and bulb. Would be much more convenient than having to remove the fixture, and hardwiring a bypass into the box. Not that I am opposed to wiring the box, I’m just lazy.


Sometimes, even if the wattage at the fixture is above the threshold, other things on the circuit can affect the switch. I have fixture with led’s that is about 30w. It works fine without a bypass, until there is a voltage drop on the circuit (vacumm cleaner). Installation of a bypass solved the problem. It appears that the constant draw that the bypass provides acts as a sort of rectifier in a non-neutral setup.

You also have to consider when the bulbs are dimmed or turned off that the wattage draw will fall below the threshold and the switch will soft reset.

For example, when my fan/light switch is off/off, the power draw is usually 2 watts. This is just the switch MCU/LED’s operating and would not work if the switch did not have a neutral connection.

The bypass is effectively a constant draw on the electrical system that allows the switch to operate no matter the connected wattage.

I agree on the screw-in bypass. Use as either a quick sanity check or as a permanent install.