Do I need a bypass with no neutral but 4 leds?

I’ve just finished installing the LZW31-SN red series dimmer. It’s a single-pole installation with no neutral (the line/hot comes in to a junction box in my attic and a single 14/2 wire goes to the switch and then back up to the lights) and it’s connected to 4 recessed LED can lights wired in series.

According to the manual, if the bulb is under 25W, a bypass is required, but then it also mentions that if you have multiple LEDs (8-12W each) then it wouldn’t be. Given I have 4 LEDs, math says I should be fine and in fact, the lights turn on and off just fine.

However, when I dim the lights, if I go lower than 45% dimmed, then the lights just turn off completely. I’m guessing this is because the total load falls under 25W when it’s dimmed that much.

So my question is - if I install a bypass will I be able to dim my lights more? And follow-up question, would I install the bypass on the first light only? For reference, these are the lights I bought.

Unfortunately I think it’s incompatible between the two. There’s only a handful of compatible dimmers on the spec sheet.

It may have to do with the MOSFET vs TRIAC differences.

Is 45% too bright? If not then you could set the minimum dimming to 45 and that would become your new “zero”.

It does not sound as if you need a bypass. That is for when the dimmer will not stay powered properly.

I think you just need to set your minimum value. Bulbs will typically not dim over the entire range the Inovelli is capable of outputting. Since bulbs vary in capability, that value is configurable.

In the dimmer’s settings, set the min to 1 and the max to 99. Then start increasing the brightness and note the level at with the bulbs start to illuminate. Then set your min value to a percent or two above that value. You can leave the max alone or adjust if it’s too bright.

The dimmer will now operate over a pseudo range. Your new 1% will be at the point where the bulbs illuminate very dimly.

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Thanks @harjms and @Bry – great to know I don’t need the bypass. I had actually done what you both mentioned already last night as a test and it does indeed work perfectly. I just thought maybe they’d dim more with the bypass if it was needed.

@smenzer - Check to see if the switch reboots when you dim down. Also, we know there’s an issue with dumb 3 way switches that have illuminated edges. I wonder if there’s an issue with the nightlight mode on these wafers.

This ^^. When you said the lights went off I presumed lights off only. When the switch reboots, the LED goes red, green, blue, so it’s obvious.

Someone here has the lights with the night light, I think. @kreene1987 , maybe?

You definitely can’t use the dimmer with an illuminated switch. @harjms may recall something regarding the nightlight style bulbs.

@kreene1987 @mamber

Do you mean the RGB bar on the switch? I just tried it and no, the switch doesn’t seem to reboot, the RGB bar shows the dim level being low even though the lights of actually off. Holding down on the “on” part of the switch the lights come back up to full power.

Now there is an issue with the night light feature when I do this…some of the lights power on normally, while others come back on in “night light” mode. (you toggle night light mode by turning the power off and on quickly). so then I end up in a weird state where 1 or 2 lights are in night light mode and the others are in normal mode. toggling off/on results in them flipping state. the only way to clear it is to turn them off and wait 5 minutes to reset itself. Not a huge deal since setting a minimum dim level avoids the issue altogether. But thought I’d mention it

Yes. It doesn’t seem like it’s rebooting.

Did you read the thread I posted? I believe @mamber addressed that.

The issue here is the slow default ‘ramp rate’ in the Inovelli dimmers. By default, they take 3 seconds to ramp on or ramp off. That’s a long time. The ‘night light’ feature in these lights is activated by turning the light on, then off, then on again within a few seconds. The slow 3-second ramp confuses the on/off logic in the night light. The solution, as pointed out in another thread, is to set the Ramp rate to 0 or 1.


Yes I have these in a neutral LZW36 installation in parallel with a fan with LED lights. Not the same application being discussed here, but I can answer any questions!

Sorry, I missed the thread in your response…yes, I read through it and I’ve made sure my ramp rate is at 0 (both manual and z-wave). It seems to be working for the most part but I still occasionally get one of the lights out of sync. The only way to fix it is to cut power to the switch at the circuit breaker panel.

I’ve also noticed that when I turn on the lights, sometimes one of the lights turns on slowly…it still comes on, but with a bit of a delay (0.5-1.5 seconds). Usually (always?) it’s the 4th light in the series, not sure if that has anything to do with it.

Edit: it has happened on several lights today, not just the 4th (sometimes the 1st, too)

I don’t know what to make of that. You have four lights wired in parallel (what I think you mean by series). Once that switch leg gets energized, they should all illuminate at the same time. But you are seeing some delay.

Yea it’s really strange…It’s almost like the power/signal is slowly getting to them to power up; which clearly can’t be the case since it happens in a different order and wouldn’t make sense anyways.

Just to be clear…the hot/line wire connects (via the switch) to the first light…then that light is wired to the 2nd light, the 2nd light is then wired to the 3rd, and then the 3rd to the 4th… which I thought was called “in series” but I’m not an expert here.

Yep, that’s clear. Just a term use discrepancy. You are using “series” to describe the lights wired to each other.

But “series” and “parallel” are also wiring configuration terms. The lights are connected one to the next, using a parallel wiring configuration. We’re saying the same thing, just describing it a bit differently. :grinning:

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I think the delay is just the characteristic of the LED driver.

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I think you are right… I see this most often if lights are turned on at minimum brightness (same with Caseta Dimmer fwiw). I typically adjust the lower turn-on threshold such that the turn on delay/timing of various lights is acceptable (which will be a bit brighter than the minimum they work at). I haven’t yet seen this if the bulbs are turned on to 100% (or other higher voltage). I also keep all lights on same circuit from same manufacturer which also helps to minimize differences.

This also happens for me when the lights are left on with the maximum brightness, though. I could enforce this I think by changing parameters 9 and 10 to be 100%, but like I said, this already happens when they’re turned off from full brightness so I’m not sure if it would help?

@harjms do you mean the LED driver on the lights themselves or the switch?

Lights themselves. The +120VAC doesn’t take long to get from B-to-C unless high resistance.

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Ok thanks… I guess I could test this if I installed a regular switch to see if it still happens?