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As I am unable to find exact answer anywhere, I am looking for some help. First of all, I'll explain the current situation. I have a freshly built appartment where noone ever lived before. We decided to go for LED lights in all rooms and all lightning zones. The wiring is done for every room and every room has its own fuse. In my country we have 220v 50 Hz. Time has come and we started looking for GU10 220v LED bulbs. We bought a set of 9 bulbs (4 or 5 W each) for one room and another set of 15 bulbs (3w each) later for second room. Also, we are using the touch switches from Livolo brand everywhere, so, no mechanical switches. None of the currently installed bulbs are dimmable, but we plan to add dimmable ones for living room.

So far, so good, everything works, except the strange feeling to my eyes on movements. I started some small research. I found out what is AC, what is DC, what is 50Hz, and after all, what is flickering and what is a cheap LED Lamp with bad LED driver inside. I also tried capturing some videos using manual shutter and the flickering was visible. Considering all this, I have some questions, but please answer them as simple as possible.

  1. Is there a technology (some box, converter, rectifier, capacitor, etc.) that can be installed already at the beginning of the circuit (after the fuse box) to drive all the lights in appartment with reduced flickering safely, while keeping in mind we're using touch switches? With technology I mean a ready made product which is safe, rated for the total wattage and is in one piece.
  2. If yes, will it work with the touch switches and the future dimmable touch switches and dimmable leds? Livolo switches are phase-cutting / Leading Edge dimmers.
  3. Will choosing a more expensive LED lamps solve the problem with flickering?
  4. If nothing can be done, except buying better LED lamps, which brands are flicker free?

At the moment we have only bought 9 + 15 leds for 2 rooms, 6 high lumen white light led lamps for bathroom, 1 high lumen led + 2 low lumen spotlights for toilet, none of them dimmable. Touch switches cost us a lot of money, so, they won't be replaced. If you require any morespecific information to answer my question, please ask and I will give everything I can find.

I just can't describe my anger on all this LED situation... if I ever knew anything similar will happen, I would have just chosen another solution, before buying...

P.S. Sorry my primitive english, it's not my native language. And thanks in advance!

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    \$\begingroup\$ You are in a bit of trouble. LED light flickering is a well recognized problem, but mostly by frustrated consumers. Manufacturers don't seem to bother with flicker characterization. I tried Google search for some-30 minutes, and couldn't find any review that would include flicker measurement. There are "methods of testing", but not reviews of actual consumer products. I hope someone will find and post some better sources here. ledsmagazine.com/articles/print/volume-12/issue-11/features/… \$\endgroup\$ – Ale..chenski Aug 7 '18 at 23:20
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    \$\begingroup\$ People widely vary in sensitivity to this, some easily satisfied by as low as 50 or 60hz, some being irritated up to around 200hz, safety issues can arise even above the point of human sensitivity if moving parts are involved. \$\endgroup\$ – K H Aug 7 '18 at 23:26
  • \$\begingroup\$ One quick solution: replace LED bulbs with old-style incandescent ones. Your health is more important. \$\endgroup\$ – Ale..chenski Aug 7 '18 at 23:45
  • \$\begingroup\$ Try using a mechanical switch. Solid-state switches may be very similar to dimmers (and not reliable with efficient LED lamps). \$\endgroup\$ – Whit3rd Aug 8 '18 at 0:38
  • \$\begingroup\$ I bought Philip brand LED from China, they too uses 220V and don't see any flicker problem. I'm using mechanical switched because they are more energy efficient. \$\endgroup\$ – Jason Han Aug 8 '18 at 1:55
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You can't easily re-engineer the existing lamps, but you can look for reviews, particularly in you area, for a better replacement.

One thing that might help while using a computer or other device with a display is to change the refresh frequency. You may have to experiment, but usually the worst setting is close to line frequency, which causes a slowly moving vertical disturbance.

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This will depend a bit on the bulbs and switches/drivers/dimmers in question and your frequency sensitivity.

Some bulbs are basically full wave rectifiers built out of LEDs, so those will go to twice the system frequency (1 flash on the positive half and 1 flash on the negative half.

Other bulbs have a PWM current regulator with output current proportional to input voltage. If they get quite hot and the electronics get messed up you definitely might end up with the output frequency becoming visible.

LEDs in pulse mode tend to have flicker become more visible at low power at a given frequency.

I believe if you try to choose quality dimmable bulbs it will probably resolve this problem. In order to make them dimmable, they have to include a bit more control circuitry and it's more likely that output PWM frequency was evaluated. Dimmable 60W equivalent LED bulbs are quite reasonably priced where I live, although those for special fixtures often still charge quite a premium.

I recommend getting or borrowing a few bulbs of different brands but the same socket type as the currently offending ones and see if they perform the same.

If this resolves the issue, it may be a problem of bulb quality. If simply putting a new bulb of the same type in the socket temporarily resolves the issue it indicates your LEDs are probably overheating and you should look at fixture choice and design, or LEDs that are designed for enclosed fixtures.

1.) This relates more to initial system design. While you may have a wiring problem, and that could hypothetically affect this, it's likely not the case, unless you choose a DC lighting system when initially wiring the house, which can simply amount to a different set of complications. Usually AC is used up to the area your LEDs are being used, at which point a larger AC to DC LED driver is used to drive multiple LED fixtures. One thing you could do is in a room with many LEDs, you can use a small amount of capacitance to cause the signal to lead a little bit and by different amounts per bulb. This is used in flourescent light flicker problems, but this will only work if you have the full wave rectifier type bulb and it's a lot of work per fixture.

2.) Performance will be inconsistent as some of these dimmers will chop up your power signal differently.

3.) Not necessarily more expensive ones, but better ones will likely do it.

4.) This will really depend on your sensitivity, but I've had fewer failures with brands that use better parts, like CREE, Luxeon or Nichia emitters. I think the companies that cheap out on design often cheap out on parts as well. That said, The price ratio from cheap off brand bulb to high end bulb is often high enough that I can just buy all the off brand bulbs until I find a good one. Some of them may also be government subsidized in your area, resulting in bulbs that appear bargain-basement cheap, but in reality are quality bulbs that were heavily subsidized due to an environmental program.

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LED light flickering is a well recognized problem, but mostly by frustrated consumers. Manufacturers don't seem to bother much with flicker characterization. See the problem overview in LEDs Magazine.

For a particular bad bulb you probably can't make much of improvement. But you can get a better, less flickering bulb if you consult with this consumer product review site, LEDBENCHMARK.

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