LZW-31 SN in 3-way shuts off when dimmer is above 93%

I have to rehash the old issue - LZW-31 SN shuts off when wired 3-way with a dumb switch and the dimmer gets above 93%

The old problem was resolved w.fw update, yet possibly not completely, still an issue for this 3-way with a pretty long wire.

Current fw is 1.48. Only happens with 1 switch out of 5 that I have in this configuration.

The LZW-31 SN in question is connected to a dumb 3-way over a long wire, maybe 40-50’, however wiring is 12 gauge. The load is x3 60W equivalent (9W) LEDs. I’m sure wiring is done correctly (checked and rechecked, I’m an el/power eng). The dimmer works as expected up to 93%. After 93% the dimmer shuts off. Exactly the same symptoms as a year ago, just 93% instead of 80%.

Ideas/guidance what to try?

The thread you referenced is a slightly different problem where the dimmer shuts off randomly. Yours is an issue where the dimmer shuts off at a particular threshold.

Is your 93% an “adjusted” 93% or a true 93% with the min and max set to 1 and 99? This has been reported before, with the solution being to set the max below where the issue occurs. Not sure if that is sufficient illumination, but that would allow you to dim to pseudo-full and not cut out.

I don’t think you can take the bulbs out of the equation since they’re LEDs. Unless all five of your installations have the same exact bulbs and quantity, I don’t think you can compare that simply.

Appreciate the reply and guidance!

The 93% is a “true” setting, no artificial “max” is set. I really don’t think setting a fake max is a solution because LEDs hum when dimmed.

I don’t think you can take the bulbs out of the equation since they’re LEDs.

Do you think swapping one (of three) or more LEDs for incandescent can allow true max?

Can you possibly enlighten what the underlying issue is? Is that a sensitivity threshold of sort? If so, have you considered making is a configurable so user can tweak it themselves for specific installations?

Fwiw, the “randomness” in shit off in the old fact finding thread reflects the quest to understand the issue. “random” was more of an emotional color thrown in, rather than a fact. I understood for great majority of reports, it was a consistently reproducible root cause resolved by a fw update. It surely solved the exact same issue cut-off-at-80% (by description) for all my 3ways but one. I hope there is a way to further tune the fw to truly resolve the issue, rather than institutionalizing a hack of faking the max. Does it make sense? Thx

My response is really more of a sense based on my experience here and working with the product. I honestly don’t know what the root cause of that issue is. Hopefully someone from Inovelli can comment if the root cause is known.

It would be interesting to see if swapping for incandescent(s) makes a difference. It just seems that with LED bulbs, a number of issues manifest themselves in certain situations. I’m not sure that the issues are fully understood (at least by me) but in some situations, some bulbs work and some don’t.

I don’t think it’s a true max issue. There is either some inconsistency between the dimmer and those bulbs in that configuration, or maybe it is just the dimmer. The problem is that there are multiple technologies in play in both the dimmers AND the LEDs.

So in your situation, if you can limit the max to 93% and still have the illumination you require, that will fix the issue. I realize, of course, that level might not be sufficient. And there are purists that want the dimmer to go to 100% whether or not they need it just because they’re supposed to work that way,so I get that.

Hesitantly tagging @Eric_Inovelli to see if there is an update on the dimmers cutting out at certain max levels. I say hesitantly because of all the tags he gets, somewhat attributable to an etiquette misunderstanding that you don’t tag someone in almost every post or they’ll start ignoring you. (<---- Rant . . . sorry to tuck this into your thread . . :roll_eyes:)

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Lol, you’re good brotha!

The firmware should be stable now – this issue was in regards to a 3-Way scenario where the bulbs would shut-off above certain levels. It wasn’t 93%, but it was around there.

Interestingly enough, I ran into a similar situation yesterday (yes, even I have problems) when I installed switches in my laundry room (mine is single pole vs 3-Way). The first issue I had was the lights didn’t shut off all the way (known issue with some bulbs) – so then I replaced them with other LED’s (I should’ve purchased some from the compatibility list, but I wanted to buy ones outside of the list so I could add to it) and I had the same problem as OP.

It was around 90% where they shut off.

Replaced them with different bulbs and it works fine.

I don’t truly know what the issue is other than there are so many different types of LED bulbs out there that there’s bound to be some issues with some.

@yxo – what you could do is swap them out with a bulb from the compatibility list (we’re almost done with a mobile friendly version of it, but if you tell my what type of bulbs you’d like – ie: A19, BR30, etc – I can send you some suggestions).

BTW, my switch at 80% is still giving off ~118V (well within spec for non-dimmable LED’s) with a 126V input on line. The % unfortunately does not seem to be linear near the top.

I recommend lowering your max and this will not be experienced.

Thank you all for chiming in, appreciate it! I definitely want to sort out the LED light bulbs compatibility first (before resorting to the fake max hack… I hear/believe you guys that it works ok, still cringe slightly if it’s the only solution.)

The current LEDs are Cree 60w equivalent standard base/shape (must be A19?). They are about 3-5 y old, from HD i think. @Eric_Inovelli - compatible LEDs suggestions/list are most welcome.

I’ll report the findings in the thread. (My experiment with w/ incandescent is slightly delayed because… can’t find 'em… my folks may still have some, planning a raid next week.)

A new version is in the works . . but this for now:

Thank you for the list! Even tho it takes away some wind from my sails - the LEDs I’m using are on the list (Cree 60W eq) indeed. Ironically, the list suggests the max at 100 [grin]. Hmmm

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I tested with incandescent bulbs and the dimmer doesn’t shut off at all, even at 100%. I also stand corrected about the LED bulbs. Not all are Cree. It’s a mix of Cree and TCP brand. It’s a bit disappointing that there is a LED compatibility issue (which really limits the applications for LZW-31SN) yet let’s call this dimmer shutoff issue resolved. Thank you all for sharing ideas and guidance!

However, while troubleshooting the shutoff issue, I ran into another problem which may not be new, but just previously unnoticed. I see that all circuits controlled by LZW-31SN in 3 way only delivering between 95-100V at the fixture when the dimmer is at true full “100%” (i.e. 99). So the fixture is slightly dimm, not at full brightness. Same for circuits that just have incandescent lights or LEDs. I tested at the switch - 122V source, 97V load (again, the dimmer is at full “100%”). At the last fixture 95V. This is an problem because

  1. the fixtures are noticeably dimmer at max and I need more light
  2. LEDs humm/buzz when not at full voltage

Should I open a new topic? Or continue this thread?

I’d like to understand the voltage drop (I’m an electrical/power eng). I can rule out wiring. It’s 12/2 and when I hard wired bypassing LZW31SN the lights get their normal line voltage.

If it’s a known issue pls point, I searched the forum before raising this.

Probably a good idea. It’s a different issue.

Whoa. this is big time inconsistent with my readings. I wonder what could be up. Definitely start a new topic!