Smooth dimming on red series

Hello all.

I just installed a couple red series dimmers but I’m finding that the dimming across the range is very staggered instead of smooth. Is there a combination of settings that smoothens the dimming? I’ve tried playing with the dimming speed and the ramp rate but I’m not getting anywhere close to my previous TP-Link Kasa and Lutron Maestro dimmers.

For info I’m finding this issue on multiple light types: generic PAR30s in pendants and recessed Liteline Slim LEDs (both dimmable).

Alex

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Noticed this too. Replaced Lutron CL Maestro digital dimmers with Inovelli Red Series and so far the dimming has been a bit weird. Gonna have to play with a bit but at the moment it seems that the Inovelli isn’t going to allow me to go below 27% while the Lutron allowed me to have the lights on very low. Also experiencing flickering at around 80% (no flickering at 100%).

Hi Eric(s) @Eric_Inovelli @EricM_Inovelli

This is also something I’ve noticed… even compared to the Gen 1 dimmers.
It is as if the dimming goes down/up one percent (step) at a time, with a delay between steps,
instead of a smooth transition.
Also, when setting minimum dim level to ~30 with LED. It appears event more evident.

Is this a hardware limitation or the way the TRIAC is driven (PWM)?
Could this be fixed in a future firmware version (after 1.41 I imagine…)

Regards,
Maxime

So this is something that I have really pressed the firmware team on and the response I have received is that it is a hardware limitation. Our engineers chose to go with a MOSFET solution rather than a TRIAC solution even though the MOSFET was more expensive. They did this so that the dimmer would be compatible with both dumb switches and aux switches. Also so that the entire device could meet FCC requirements and not just the RF module.

Having said that, there are varying bulbs that may perform better with the device than others. So your experience may be different from other users.

Hi @EricM_Inovelli,

Thanks for the info! I believe my solution will be to set the ramp rate to instant. This way, there is no jagged dimming at all. Furthermore, when dimming manually at the switch, It is not too bad to see the “steps” in dimming.

Regards,
Maxime

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I am jumping into this a little late but then again I’m still new to Inovelli… I have to complement Inovelli and this community as I am really excited to read all the discussions and of course use the products. Bravo! :sunglasses:

I too am experiencing significant “steppy” artifacts while dimming. I have not been able to improve it much no matter what setting I adjust. I have noticed that as I raise the minimum dimmer level preference I can make the situation worse. But even with a minimum of 1% the artifacts clearly are visible — and sometimes really objectionable. I can second @MxMLssR’s report that right around the 30% value I see the worst steps. Strangely this does not change with however the minimum or maximum level preferences are set in the driver. Any value I set in Hubitat between ~28% up to ~40% will look particularly bad with things smoothing above. This does suggest that perhaps there is some driver/firmware work that can be done to improve the situation.

Furthermore I observed yesterday (and can reliably repeat) that dimming can actually reverse direction before settling. My controller is Hubitat with the latest update and I am using the Inovelli supplied drivers with the latest firmware installed on all dimmers. With any significant (approximately 10% or more) minimum dimmer level preference, dimming down from any higher value to 14% momentarily will settle darker than the desired level but then pop back up again a moment later. I can see this with incandescent and LED loads so I do not expect the quantization problem to be within the bulbs.

I can see and measure this when using any light source. LED bulbs (known to perform very well on other dimmers), incandescent bulbs (with short and long filaments), and halogen bulbs of various types including PAR bulbs in recessed downlights. I am very curious how others have improved their situations and how @EricM_Inovelli and @Eric_Inovelli can keep pushing the firmware team and/or a future hardware revision to smooth things even more. Aside from this complaint the Inovelli Red Series dimmers are second to none and perform well engineered. So I am hopeful that there are some potential improvements (with us as happy guinea pigs? :wink:)

Perhaps all of this is caused by some rounding errors? Or perhaps there is some sort of dither or other driver trickery that can be added to the firmware to smooth our dimming?

Thanks,
Richard

PS here’s a list of bulbs I have tested. All experience the steppy dimming artifacts. Some are poor dimming performers in general. So do not take this as a list of recommendations either good or bad but as a list of bulbs that clearly reveal this issue. At work we use the EA, Cree Pro, and Philips bulbs whenever we cannot use incandescent or halogen so I know them to be trusted dimming performers in other contexts.

  • Any/All Halogen Bulbs (PAR, JDD, and Eco style A shape)
  • Any/All Incandescent Bulbs (candelabra, A shape, standard filaments)
  • Any/All Long Filament Incandescent Bulbs (these should have the most “smoothing” effect on any steppy dimming yet the steps are so sharp in this case that even this ole’ trick fails)
  • Emery Allen EA-E26-9.5W-001-279F-D
  • Emery Allen EA-E12-4.5W-001-279F-D
  • Maxlite EFF8.5T12D927/JA8
  • Maxlite E17A21D927/JA8
  • Maxlite 103FF4B10D927
  • Maxlite EF4B10D927/JA8
  • Cree Pro B11-60W-P1-27K-E12-U1
  • Cree Pro TA21-16027MDFH25-12DE26-1-E1
  • Philips 5.5B11/PER/927-922/CL/G/E12/WGX 1FB T20 (perhaps the biggest surprise since I know these to dim to very weak levels and smoothly)

Wow - that is a nice list of test bulbs. I was about to go pick up some Cree’s today and test them out to fix my leaky light problem with cheap bulbs.

From what I can tell, I MOSFET should give more control to the firmware than a TRIAC. It can switch faster and it does not natively stay switched on until the a/c frequency drops to zero. From firmware, a MOSFET should be able to do leading or trailing edge power. But, I could be completely wrong about that. :slight_smile:

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If a MOSFET controlled AC dimmer were indeed firmware/software switchable from leading to trailing edge then I would be very excited to test such a feature. Wow what doors that would open. I concur with you that the MOSFET design should enable an extended range and enhanced precision of control of the switched AC waveform. Here’s hoping.

Concerning bulbs, I should say that the list I posted is for example only and not necessarily recommended. Your mileage may vary. On the LZW31 dimmers so far, using LED bulbs, I get the best results from anything Emery Allen and the Philips Warm Dim line. That mouthful of a product code from Philips has one key clue in the middle — the “927-922” section. That means it is part of their warm dim collection which will shift in color temperature as it dims down from 2700K to 2200K (or at least that is what is claimed, my color meter confirms the actual range is a bit higher than that). All the Maxlite bulbs look good and Cree bulbs look great but neither dim nicely at all at least in my limited testing. I encourage you to try them and post your findings here!

One other thing I should say — anything incandescent or halogen dims in such a manner that is in another class entirely. If you want the smoothest possible dimming then there is no substitute so far.

– Richard

@rpulivella those Philips warm dim bulbs look interesting! That’s actually the exact type of lighting I was looking for.

Are you saying they don’t work well right now with the inovelli dimmers? I will be trying out the recessed retrofit bulbs

Ah, nevermind, I managed to find some of the Philips Warm Dim bulbs locally. I see what you’re saying. They do dim nicely to very low levels and the color temp shift is nice, but they also seem to dim less smoothly compared to other bulbs. Maybe because the temp shift makes the effect more apparent.

Hey guys, this is something that we have discussed with the manufacturer a few times and have been told that it is a hardware limitation. They claim it is with the hardware and firmware programming that makes it possible to offer dumb switch & aux switch support.

A “kind of” workaround is to set parameters 1-4 to something low. I would say setting 1, 3, & 4 to 0 or 1. I set parameter 2 to something a little higher to make dimming at the switch easier. Setting it to 2 seems to work.

Anyway, probably not the answer you want to hear, but wanted to provide some options you could try.

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I really hope this can be improved some day. It’s one of my very few strong criticisms of the Inovelli dimmers so far and I am a tough critic in this area.

I agree with @EricM_Inovelli’s workaround. I experimented with something like this and eventually landed with parameters 1–4 being set to 1, 4, 1, 1 respectively. That preserves convenience when manually dimming at the switch but keeps everything else fast. Most of my fade times are set by scene or by Rule Machine rules so when it is important the fade times are explicit.

My wish here would be to split the up and down times so that the dims from any positive value down to zero (0, aka off) would be longer than the other way around. When a light is on at some visible value adjusting its intensity brighter or darker should go at matching rate. But when triggered by certain scenes or manually sent to off it would be nice to slow that fade down so that there is some light when exiting a room.

Anyway I still prefer the Inovelli dimmers far and away above any other wall box dimmers I have used in my home. I am confident that if any team out there will be able to refine/improve/perfect this sort of product its Inovelli. Let’s hope this feature request moves high up on the chart!

– Richard

I will definitely keep pushing back to see if there is anything we can do. We really appreciate feedback from our customers and use it to further refine our products. A lot of our Gen 2 features are specifically from feedback from our customers regarding our Gen 1 stuff.

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Awesome. Your Gen 2 products are fantastic! I look forward to whatever comes next!

Checking to see if there is any current work on this issue @EricM_Inovelli . I’ve been using the dimmer successfully for smart bulb control. I’ve now set up a few for regular non smart bulb control and notice the stepping issue. To be frank, these dimmers do not work well at all at dimming, and do not match either higher or lower-end competition. (I’ve tried with a few bulbs.)

Throwing in my $0.02 CAD as well :slight_smile: :canada:

There’s so much I love about these dimmers — the vast configurability, the tactile response, the general community / developer engagement… it’s all top-notch.

The only thing that’s a substantial miss, to other’s points, is the dimming. It’s rough. I work as a lighting designer and qualities like dimmer curve and smoothness are very important to me, and both of these are worse in the current Red & Black-series dimmers than I’ve seen in any other product. I’ve installed ~30 of these dimmers to supply a variety of sources, from NSP 12V MR16’s, standard line voltage GU10’s, LED & Halogen Source 4 Mini’s, custom LED downlights… the whole gamut. The dimmers handle the different load types like a champ, but they’re all equally steppy with whack dimming curves, regardless of how the dimmer has been configured through the multitude of advanced options. I believe this one (and unfortunately very critical) component of the device’s design necessitated a little more polish.

I’m curious to know what differs in the dimming technologies between the Gen 2 dimmers and the LZW-36, as the latter dims wonderfully smooth regardless of transition time, min/max settings etc. It behaves just like a dimmer should, in my unrequested opinion :tipping_hand_man:

I remain hopeful that something can be done on the software side to literally smooth this out, as it’s the only niggle I have with these otherwise stellar products. Pity it’s such a big one. At the end of the day, the key thing that a dimmer needs to be able to do well is dim.

Very warmly,

r

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I really hope so too, I’ve got over 60 installed, and in one room I have an old lutron digital dimmer. It’s so smooth…the difference is night and day.

That said I think I read some time ago that Inovelli chose to use mosfet vs some other kind of dimming implementation (pwm?) dimming and this is the best they could do.

Maybe, just maybe there’s something they can still push the mfg to work on improving. It is after a core function that all isers would benefit from enhancing vs smart bulb functionality or similar niche features/improvements.

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We have discussed this with the manufacturer and it seems to be a limitation of the mosfet (vs triac) dimming. We had to go with the mosfet to include some of the advanced features (even though it is a more expensive option). To have the dimming process seem smoother, you can try to change the ramp rate / dimming speed to 2 or 1. It seems to make a big difference for some.

Thanks for the update. I’m not trying to be a jerk, but this dimmer should not have passed the first QA tests. The dimmer doesn’t dim well, in fact I’ve never seen one that stutters in such a manner. All the advanced functionality is nice (I bought my first one for smart bulb mode), but should not be at the expense of smooth dimming. Changing parameters makes some difference, but does not eliminate the issue. Hopefully you are developing a 700 series dimmer that does not have this dimming issue.

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I really feel like the triac/mosfet difference is irrelevant here and we’re hitting some limitation or unfortunate programming for a digital to analog conversion. The input to output curves on a mosfet are smooth and do not jump. Does the software jump directly from one integer value to another when it’s dimming?

I agree that the dimming quality is very frustrating and I specifically warn people about it as much as I recommend the product overall.