Author Topic: LED Battern lighting is making my video flicker  (Read 3631 times)

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Offline Automate007Topic starter

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LED Battern lighting is making my video flicker
« on: May 22, 2023, 12:29:53 pm »
Hi I need brain stormers. I am building an office / studio / steaming channel for my wifes little cake business. The 2 rooms out of 4 built and now finished are super clean and bright and installed 8 to 10 of these https://www.sal.net.au/products/interior-led-lighting/led-linear-battens-and-profiles/BLADE-SL9709-TC in each room. The idea as we were working from home with studio lights everywhere and now we build this decided to blast heaps of light in the room eliminating studio lights so when she has a room full of students we don't have wires everywhere.

We powered up security camera's, logitech webcams for streaming and phone camera's. ALL produce flickering and unfortunately none of the devices have an option to set a frequency. Logitech can switch from 60hZ to 50hZ but it still flickers but not as bad.

The outlay for all the lights unfortunately has me in a position where budget won't allow to buy a pallet of other lights so now I'm thinking would it be an option to buy 1 more , open it up to get to the driver and modify it somehow to stop it from flickering on video.

I would have thought going from AC power to LED that there wouldn't be a frequency issue. I was convinced that Alternating current would get rectified to DC to power the LED's but clearly I was very very wrong, What am I missing here. Please any idea's or help would be greatly appreciated. Happy to disconnect the light driver and put in something else to power the fixed LED's inside this slimline batten to stop the frequency flicker all together 
 

Online wasedadoc

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Re: LED Battern lighting is making my video flicker
« Reply #1 on: May 22, 2023, 12:48:36 pm »
Yes the AC is rectified but if there is no smoothing capacitor there will be peaks and nulls.  Each at twice mains frequency if full wave rectifier.
« Last Edit: May 22, 2023, 12:51:35 pm by wasedadoc »
 
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Offline Automate007Topic starter

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Re: LED Battern lighting is making my video flicker
« Reply #2 on: May 22, 2023, 01:09:44 pm »
So in that case that gives me hope. I will buy another light to experiment with before I even think about modifying each one. So excuse my novice questions but integral electronic circuits is not my forte! Ok so where would the caps go roughly? Are they across the DC output to the lights or before that somewhere else on the circuit usually?

Once I get the spare batten I will try to draw out the circuit or provide pics of the board for further help
 

Offline jmelson

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Re: LED Battern lighting is making my video flicker
« Reply #3 on: May 22, 2023, 03:08:54 pm »
I built my own ceiling lights for the kitchen and used commercial LED lighting power supplies.  I know they have big capacitors in them becuase the lights fade out for a second when turned off.  These lights have 20 LEDs in series and so drop about 70 V.  The power supplies are Thomas Research Products LED25W-72-C0350 from Digi-Key.
So, these ought to eliminate flicker, too.  These supplies will run strings at 350 mA from 36 - 72 V, so that is about 10 - 20 LEDs in series.

Jon
 

Offline Benta

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Re: LED Battern lighting is making my video flicker
« Reply #4 on: May 22, 2023, 11:38:57 pm »
First, for a studio, a CRI of ~80 for your LED lights is lousy. Sorry, but it can get too cheap.
Second, for this kind of application, I'd never go for LEDs. For beautiful colour rendering, halogen rules.

Now for a solution. Can it be (it's about baking, after all) that you have three-phase service?
If so, patterning your lights onto all three phases might solve it. That's then just a rewiring issue.
 

Offline james_s

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Re: LED Battern lighting is making my video flicker
« Reply #5 on: May 23, 2023, 12:10:15 am »
This is common, LEDs have negligible phosphor persistance and no thermal mass like tungsten filament so if they receive pulsating current they will flicker. When the flicker of the lighting beats with the camera shutter frequency you get rolling bars and other artifacts. Your only solution is either replace the lights, or replace or modify the drivers to add some smoothing. It *might* work to simply add some capacitance across the output of the driver.
 

Offline Benta

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Re: LED Battern lighting is making my video flicker
« Reply #6 on: May 23, 2023, 12:19:49 am »
It *might* work to simply add some capacitance across the output of the driver.
More likely to let out the magic smoke, after I've seen how primitively those drivers are built. But give it a try. It can only burn the house down.
 

Offline james_s

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Re: LED Battern lighting is making my video flicker
« Reply #7 on: May 23, 2023, 12:21:13 am »
It *might* work to simply add some capacitance across the output of the driver.
More likely to let out the magic smoke, after I've seen how primitively those drivers are built. But give it a try. It can only burn the house down.

I don't think it'll burn the house down. Either it will reduce the flicker or it will let out the magic smoke on the bench. First thing I would do is reverse engineer the driver though, and then work out the best way to remove the flicker.
 

Offline Automate007Topic starter

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Re: LED Battern lighting is making my video flicker
« Reply #8 on: May 23, 2023, 12:49:10 pm »
Yeah hopefully to get another and pull it apart for smoothing cap on the bench. I'll have to hook up an osciliscope to play with different capacitance and minimise or eliminate the ripple.

The 3 phase idea above ..... hmmmm that one is interesting but not able to do that as 1 phase is going to a 3 gang switch powering the lights and no way to separate the 3 switches on different phases easily.

Thanks guys but I think cutting the ripple will ultimately fix the issue..... I think I would like to retain all the smoke in all the right places.... I'll update this post once I get more circuit info
 

Offline Automate007Topic starter

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Re: LED Battern lighting is making my video flicker
« Reply #9 on: May 23, 2023, 01:10:27 pm »
Yeah I thought the same as you with the CRI rating but they are at 5700K really bright and white. It's just flicker that is killing me.

Keep in mind for photography and product shots I've got that side professionally covered as I am a photographer but the standard ceiling (flickering) lighting is when we have students watching a large screen of the teacher doing detailed closeup work in real-time on the screen or for streaming classes on Facebook live (720p) .... Simple 3 x logitech webcam setup with OBS studio. CRI is not critical here and the colour of these SAL lights is really really good and even. No magenta, blue or yellow tint cast that is visible but they are super white light bouncing off bright vivid white walls..
« Last Edit: May 24, 2023, 10:25:43 am by Automate007 »
 

Offline John B

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Re: LED Battern lighting is making my video flicker
« Reply #10 on: May 23, 2023, 10:05:20 pm »
The integrated power supply will be very basic. More than likely it uses a low capacitance input switching supply (for good power factor), but that results in the output waveform with DC + a large amount of AC ripple, hence the flicker.

You'll probably need to invest in some high CRI panels without integrated power supplies, then use a good quality LED driver that uses active power correction and gives an output which is at least as clean as a regular DC adapter. I've always just gone to meanwell for supplies and never had an issue with them. You can also get ones with integrated dimming control.

 

Offline Automate007Topic starter

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Re: LED Battern lighting is making my video flicker
« Reply #11 on: May 24, 2023, 11:22:40 am »
Ok had to quickly get this done as its late and I've got an interstate trip in the morning. Ok I have found its outputting around 115VDC to the LED'S. There appears to be a 160V 100uf capacitor which looks like on the output side. When I look at the ociliscope output I'm measuring a 11.4V ripple at 100hz. Is this just a question of when I get back to remove the 100uf cap and install a larger size uf instead? How can I calculate what size cap I need?
 

Offline Automate007Topic starter

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Re: LED Battern lighting is making my video flicker
« Reply #12 on: May 24, 2023, 11:24:31 am »
These are some pics of the board
 

Offline Automate007Topic starter

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Re: LED Battern lighting is making my video flicker
« Reply #13 on: May 24, 2023, 11:48:26 am »
Oscilloscope
 

Online wasedadoc

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Re: LED Battern lighting is making my video flicker
« Reply #14 on: May 24, 2023, 12:03:09 pm »
It looks to me that the +ve side of the 100uF 160 Volt electrolytic is on the +ve output of the 4 diode bridge rectifier on the incoming mains.
« Last Edit: May 24, 2023, 12:06:24 pm by wasedadoc »
 

Offline Stray Electron

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Re: LED Battern lighting is making my video flicker
« Reply #15 on: May 24, 2023, 12:27:42 pm »
     A friend of mine is a semi-professional photographer and the LED lighting in his photo studio was producing bars on the photos that he was taking.  The LED were run directly from the 60 HZ AC main so they were strobing at 120 Hz rate and the camera was capturing the strobing.  We looked at the specs for the LED bulbs and we found that they would also run from pure DC. The LED lighting was on a AC circuit with nothing else on it so we went into the circuit break box and added a bridge rectifier to the output of that particular circuit breaker and then added a large filter capacitor to the bridge output and then connected the lighting power circuit to that. So long story short, the circuit that powers the LED lighting is now pure DC.   It worked like a charm!  The lighting circuit actually doesn't draw much power and we checked the RC time constant of the cap that we used and there is almost no voltage drop during the zero-crossing of the AC input. 

   We stuffed the capacitor and the bridge rectifier inside of the circuit breaker box so we didn't need to make any changes to the wall or any of the existing wiring.  The building inspectors might not like the idea of the extra items inside of the CB panel or of the DC wiring, but it works!
 

Offline Automate007Topic starter

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Re: LED Battern lighting is making my video flicker
« Reply #16 on: May 24, 2023, 12:46:44 pm »
That's brilliant but I will need to research that a bit more cause here in Australia we are 240vac 50hz. But light input does say 220 - 240v 50hz
 

Offline Automate007Topic starter

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Re: LED Battern lighting is making my video flicker
« Reply #17 on: May 24, 2023, 12:55:51 pm »
It looks like yes the +v of the cap is connected to the +v output on the dc side of the bridge.... isn't that right? What I'm thinking it's got a smoothing cap but not big enough? Is it as simple as desoldering this 160v 100uf and trying around 1000uf ?
 

Offline james_s

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Re: LED Battern lighting is making my video flicker
« Reply #18 on: May 24, 2023, 06:36:51 pm »
It looks like yes the +v of the cap is connected to the +v output on the dc side of the bridge.... isn't that right? What I'm thinking it's got a smoothing cap but not big enough? Is it as simple as desoldering this 160v 100uf and trying around 1000uf ?

That's exactly how I'd expect it to be arranged, that's clearly a SMPS.

Try increasing the capacitor value and see what happens. 1,000 may be a bit much, 470 is closer to what I'd expect. You have to be careful of inrush of a large low ESR capacitor popping the fuse or blowing the bridge.
 

Online tunk

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Re: LED Battern lighting is making my video flicker
« Reply #19 on: May 24, 2023, 06:52:04 pm »
No expert, but it could look like there's not much smoothing on the primary side
(what's the capacity of the two brown caps?). This could explain the 100Hz ripple.
 

Offline james_s

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Re: LED Battern lighting is making my video flicker
« Reply #20 on: May 24, 2023, 07:22:02 pm »
Smoothing on the primary side is exactly what we're talking about. The bulk filter capacitor after the rectifier. There's only one of them.
 

Online tunk

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Re: LED Battern lighting is making my video flicker
« Reply #21 on: May 24, 2023, 08:37:35 pm »
To me it looks like the 100uf/160V cap is on the secondary (Australia uses 230Vac).
Note that PCS are rotated (the switch is on the left in the top photo and on the right in bottom photo).
 
 

Offline John B

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Re: LED Battern lighting is making my video flicker
« Reply #22 on: May 24, 2023, 09:13:24 pm »
I tried to modify an LED driver with much the same layout as that, but even adding primary and secondary capacitance, it simply didn't clean up the output waveform enough.

I ended up ripping out the integrated drivers and running them as passive panels.
 

Offline Automate007Topic starter

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Re: LED Battern lighting is making my video flicker
« Reply #23 on: May 24, 2023, 09:15:53 pm »
Yes the pics are rotated note the switch position. Also the switch makes the led change temp. From warm to daylight 3000k to 5700k. The 160V 100uf is directly after the rectifier and on the +/- DC rail. I also would imagine that if it were on the primary side of the rectifier at 160V rating it wouldn't last very long if it were on the 240vac side..... yes?

Question can I desolder the caps off a couple of the other lights and add it to this circuit. By memory if I run the caps in parallel ... say 2 more added in parallel does that make it the same as a 160v 300uf?
« Last Edit: May 24, 2023, 09:20:35 pm by Automate007 »
 

Offline Automate007Topic starter

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Re: LED Battern lighting is making my video flicker
« Reply #24 on: May 26, 2023, 09:40:51 pm »
Ok I have scavenged a few caps from the other lights. This is what I have found
100uf = 11.4v ripple
200uf = 7.4v ripple
300uf = 5.2v ripple

Also this driver is outputting 120VDC and measuring 0.17amps on the input side

So I'm going to assume around a 1200uf will get me down to about 1v ripple?

Hmm it's physically too big and expensive for 20 lights to go this way. Any idea's?
« Last Edit: May 26, 2023, 09:43:41 pm by Automate007 »
 

Offline John B

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Re: LED Battern lighting is making my video flicker
« Reply #25 on: May 26, 2023, 10:24:01 pm »
You say this is for a work/business context. There's a few things to keep in mind. I would be careful about modifying mains powered stuff (especially cheap stuff) then using them in an unattended situation. It's also a legal problem.

The safest way would be to buy an off the shelf AC/DC constant current LED driver which is capable of outputting sufficient voltage. This way all the mains isolation and certification is taken care of.

For rough figures, you'd be looking at $50 per driver, 1 per panel.

Another option is to cut the losses on these panels and invest in a more standardised system. Ie 1200mmx300mm passive panels running at around 36V, with external drivers. This way you can pick the panels you want, specifically the highest CRI ones you can get, then pair them with some brand name drivers. Panels you buy will come with drivers, but will most likely have the high AC ripple issue.
 

Offline Automate007Topic starter

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Re: LED Battern lighting is making my video flicker
« Reply #26 on: May 27, 2023, 01:20:43 am »
You say this is for a work/business context. There's a few things to keep in mind. I would be careful about modifying mains powered stuff (especially cheap stuff) then using them in an unattended situation. It's also a legal problem.

The safest way would be to buy an off the shelf AC/DC constant current LED driver which is capable of outputting sufficient voltage. This way all the mains isolation and certification is taken care of.

For rough figures, you'd be looking at $50 per driver, 1 per panel.

Another option is to cut the losses on these panels and invest in a more standardised system. Ie 1200mmx300mm passive panels running at around 36V, with external drivers. This way you can pick the panels you want, specifically the highest CRI ones you can get, then pair them with some brand name drivers. Panels you buy will come with drivers, but will most likely have the high AC ripple issue.

John your 100% right. Stupidly I Ordered these lights and installed before I should of tried 1 and assess with the camera's when we were at the building stage. But I do have 2 jobs and time was not on my side and rushed into it. Lesson learnt. My issue is also I was stupid to think going LED that there would be no frequency flicker..... I assumed wrong! I'm now torn as the ceiling is a concrete slab with no where to really hide drivers and not easy to mount LED panels to concrete let alone rerun all the cabling. Aaargh I'm so annoyed with myself

My issue now is If I do buy drivers and tie it into the existing lights how can I be 100% sure they are ripple free dc output drivers?  Anyway this is a loosing battle and only have my self to blame.

Thanks guys for all the responses. Good advise given and hopefully this will help the next guy similar to my predicament!

Advice. Buy a few different options .... test.... then buy bulk.
 

Offline John B

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Re: LED Battern lighting is making my video flicker
« Reply #27 on: May 27, 2023, 02:23:27 am »
My issue now is If I do buy drivers and tie it into the existing lights how can I be 100% sure they are ripple free dc output drivers?  Anyway this is a loosing battle and only have my self to blame.

I have the most experience with the HLG series of drivers from Meanwell. They are more like AC/DC power bricks in their output waveform, ie clean DC, with switching noise. Also the datasheet for these types of drivers will give a Vpk-pk figure which you can gauge how much ripple you'll be getting, typically a few hundred mV. This will include the switching noise up to 20MHz, it wont be mains frequency ripple.

The problem is these integrated panels will often run fairly high voltage for efficiency. While there's nothing technically difficult about driving them, actually finding suitable equipment at a cost-effective price will be difficult. For example it wouldn't be too technically difficult to make your own, or buy a linear constant current module for each panel, then feed each panel with ~160V DC from a single AC/DC power supply, that's outside the extra low voltage specification, so there's much less choice out there in buying those power supplies. It's still legally a no-no at that voltage  ::) Bloody red tape.

Then you have to weigh up sinking money into this specialised voltage setup, and whether you'd be able to repurpose the equipment for anything else. At least your typical 36V panels and drivers can be mixed and matched, and reused. You could even use the same principle of cheap, small low drop out linear drivers for each panel and a single AC/DC converter. Assuming you don't need dimming or colour control. That's real can of worms. I'm building something similar to your needs with dimming and colour control. It's a pain.

Also with passive panels, you could just run the wire to each panel and have drivers in a cabinet somewhere to simplify the mains wiring. Constant current drivers will be compensating for any voltage drop in the wires, not that there's much with LED panels, especially if you use 1.5mm2 wire or something.

It's a tough call. Can you salvage the existing lights for a shed or patio or something?
 

Offline John B

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Re: LED Battern lighting is making my video flicker
« Reply #28 on: May 27, 2023, 02:42:37 am »
Just another thought on the idea of a single AC/DC power supply feeding multiple constant current drivers - you don't even need 1 driver per panel. Large strings of LEDs actually balance themselves pretty well in parallel when run at modest powers and currents. Meaning if you had panels than ran at 700mA typically, a 1.4A driver could power 2x panels in parallel. You don't want to go much further though, just in case an LED ends up shorting on one string then that driver ends up dissipating too much heat. I've actually been running 4x 60V panels that way for several years and there's been no issues.

Colour temperature adjustable panels actually work in this way. There's 2x strings of LEDs, one at ~2700K, then one at ~6000K. Then a constant current driver either is applied to one or the other, or both strings.
 

Offline Automate007Topic starter

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Re: LED Battern lighting is making my video flicker
« Reply #29 on: May 27, 2023, 03:37:19 am »
Just another thought on the idea of a single AC/DC power supply feeding multiple constant current drivers - you don't even need 1 driver per panel. Large strings of LEDs actually balance themselves pretty well in parallel when run at modest powers and currents. Meaning if you had panels than ran at 700mA typically, a 1.4A driver could power 2x panels in parallel. You don't want to go much further though, just in case an LED ends up shorting on one string then that driver ends up dissipating too much heat. I've actually been running 4x 60V panels that way for several years and there's been no issues.

Colour temperature adjustable panels actually work in this way. There's 2x strings of LEDs, one at ~2700K, then one at ~6000K. Then a constant current driver either is applied to one or the other, or both strings.

Ok now thinking out loud.

Forget the 3 colours I only need the 5700k LEDs  so this eliminates the secondary warm LED wire.

So the 320 White LEDs by themselves draw 0.380amps at 120VDC.

The shop front I can live with the lights on the concrete ceiling as they are...  in reality we won't be running any live streaming in there for a while so for now I can concentrate on the teaching room which has a a new gyprock ceiling and a cavity from the mezzanine above. Now that I have completely dismantled 1 light I can see a number of options.

1. Find 2 x 470uf (or higher) caps under 18mm diameter each and run them in parallel in the existing board space . It will be tight but should fit but not sure how low I can get the ripple

2. Remove the cap and extend with a 2 core cable out of the light fixture and into the ceiling cavity and mount the larger 1200uf cap in a sealed junction box. Crazy but do able

3. If I unscrew the ends I can slide out the diffuser in which I have a cavity between the diffuser and LED board of 21mm . I could in theory solder the caps directly to the DC plug feeding the White LEDs and glue(silicon blob) the caps in there on the LED aluminium panel and parallel 2 (or 3) x 470uf (18mm dia) in there not modifying the existing driver ..... do I Remove the original 100uf or keep it in there?

4. Or Remove the existing driver board altogether and extend the 0v and 120v wires from the panel to the outside and connect it to a good driver in the ceiling cavity.  This is the safest option I think.

Maybe next year if the business does ok then I'll rip em all out and get expensive CRI rate LED panels but for now it's all we can afford as we have literally put in all our savings to make this home hobby business into a reality. We will succeed but covid killed us for 2 years with no cakes or functions and all our stock from manufacturers stopped.... resulting in no income for 2 years...  so lucky my day job carried us through till now? I know get the violins out but this is my dilemma! Just trying to catch a break for once
« Last Edit: May 27, 2023, 03:42:04 am by Automate007 »
 

Offline John B

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Re: LED Battern lighting is making my video flicker
« Reply #30 on: May 27, 2023, 06:47:19 am »
Understood, you also need to consider the time and effort, and even the expense of say 20 junction boxes. Let's say they're $10 each, that's already $200 of budget on useless plastic.

What would be your budget for fixing everything?
 

Offline Automate007Topic starter

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Re: LED Battern lighting is making my video flicker
« Reply #31 on: May 27, 2023, 07:02:58 am »
True. Keep in mind that room has 8 lights. I can do about $400 to fix just that room for now
 

Offline John B

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Re: LED Battern lighting is making my video flicker
« Reply #32 on: May 27, 2023, 07:35:18 am »
There's one last option that I can think of, which Stray Electron mentioned at the start of the thread. Keep the existing drivers as they are and then power the lights with DC, or rectified mains.

I'll have to follow up on this later, but perhaps a 1.5 kVA step down transformer 240V -> 120V used for powering US equipment, then rectified and filtered. This will provide up to 170V DC with ripple depending on the output capacitance. Rectifying the mains is probably an option, but ~340V DC low impedance is getting a bit sketchy.

A 120V DC power supply is also an option, but it's going to be out of the budget.
 

Offline Automate007Topic starter

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Re: LED Battern lighting is making my video flicker
« Reply #33 on: May 27, 2023, 12:21:55 pm »
There's one last option that I can think of, which Stray Electron mentioned at the start of the thread. Keep the existing drivers as they are and then power the lights with DC, or rectified mains.

I'll have to follow up on this later, but perhaps a 1.5 kVA step down transformer 240V -> 120V used for powering US equipment, then rectified and filtered. This will provide up to 170V DC with ripple depending on the output capacitance. Rectifying the mains is probably an option, but ~340V DC low impedance is getting a bit sketchy.

A 120V DC power supply is also an option, but it's going to be out of the budget.

Thanks John for your time. I finally found a 680uf 160v cap that is 18x40 from elements14. I have worked out I can make 2 fit in a cavity beside the driver .... 1 on each side. I will try with 1 680uf + the 100uf on the original board might just be low enough that my cams can deal with it. If not I'll add a second 680uf on the other side. If that doesn't work. I'll remove these lights and will have to search for flicker free panels that will cover the holes of these units.

Hoping I will get thd caps delivered by early next week and will report back my findings.
 

Offline Automate007Topic starter

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Re: LED Battern lighting is making my video flicker
« Reply #34 on: June 06, 2023, 10:47:30 am »
There's one last option that I can think of, which Stray Electron mentioned at the start of the thread. Keep the existing drivers as they are and then power the lights with DC, or rectified mains.

I'll have to follow up on this later, but perhaps a 1.5 kVA step down transformer 240V -> 120V used for powering US equipment, then rectified and filtered. This will provide up to 170V DC with ripple depending on the output capacitance. Rectifying the mains is probably an option, but ~340V DC low impedance is getting a bit sketchy.

A 120V DC power supply is also an option, but it's going to be out of the budget.

I have received the 680uf caps today and applied 1 in parallel with the 100uf and it takes 2 seconds to turn on and about 2 minutes when switching off to get down to 0vdc.

To make matters worse even at a 3v ripple it still flickers. Not as bad but still unacceptable.

I'm so confused as to my best option now that will work 100% . I have now resigned to the fact there is no way to fix this . Anyone can point to a safe solution that has no ripple and is hopefully under $100 per light. I'm all ears!
 

Offline John B

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Re: LED Battern lighting is making my video flicker
« Reply #35 on: June 07, 2023, 12:45:30 am »
Yeah that sounds like my experience, you're trying to modify an AC/DC topology that inherently has a fair bit of ripple. The best solution that I can think of is to look at using a CC LED driver, and remove the existing drivers from the panels, ie convert them to passive panels.

Consider something like this:
https://au.mouser.com/ProductDetail/MEAN-WELL/XLG-100-L-AB?qs=sGAEpiMZZMvV8Y9YugmIggXPjVR9iwOZ2ARXrvaN0alPoJ9X1te3Xw%3D%3D

$55 in single qty and $50 in tens. The current output has 3% ripple, note that your voltage ripple will result in a much larger current ripple due to the non-linear nature of LEDs, and current roughly equals light output. One of these drivers could be used to drive 2x panels in parallel. I would add a small amount of balancing resistance per panel, perhaps a 1R to equalise the current sharing between panels. The driver would be set to output around 700 - 750mA, best to be a little conservative on panel power.

Note the ending code on the meanwell models. They will often have an A, B, AB or another code. These denote the current output control / dimming function. Without any adjustment, the XLG 100 L will want to output 1A of current (500mA per panel )which would probably damage the LEDs. The "A" version has an integrated trimpot which you would use to set each driver to around the 700mA level. However this seems to be out of stock in most places. The AB model has a pair of wires to control the "3-in-1" dimming function. You can use a 0-10V DC signal, a PWM signal or use a potentiometer (probably the safer bet). The AB model seems to be fairly available at the moment.

0.75A at 120V equates to a 160R resistor, which you could use to set up the driver and test the current before connecting them to panels to avoid panel destroying mishaps.

I'd buy a single unit first just to test the concept, then buy another 10x @ $50.

It's a little tricky to find other suitable drivers with V/I characteristics, at a good price point, availability etc.

I also encourage you to check the datasheet for anything I might have missed.
 

Offline Automate007Topic starter

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Re: LED Battern lighting is making my video flicker
« Reply #36 on: June 07, 2023, 01:39:27 am »
Yeah that sounds like my experience, you're trying to modify an AC/DC topology that inherently has a fair bit of ripple. The best solution that I can think of is to look at using a CC LED driver, and remove the existing drivers from the panels, ie convert them to passive panels.

Consider something like this:
https://au.mouser.com/ProductDetail/MEAN-WELL/XLG-100-L-AB?qs=sGAEpiMZZMvV8Y9YugmIggXPjVR9iwOZ2ARXrvaN0alPoJ9X1te3Xw%3D%3D

$55 in single qty and $50 in tens. The current output has 3% ripple, note that your voltage ripple will result in a much larger current ripple due to the non-linear nature of LEDs, and current roughly equals light output. One of these drivers could be used to drive 2x panels in parallel. I would add a small amount of balancing resistance per panel, perhaps a 1R to equalise the current sharing between panels. The driver would be set to output around 700 - 750mA, best to be a little conservative on panel power.

Note the ending code on the meanwell models. They will often have an A, B, AB or another code. These denote the current output control / dimming function. Without any adjustment, the XLG 100 L will want to output 1A of current (500mA per panel )which would probably damage the LEDs. The "A" version has an integrated trimpot which you would use to set each driver to around the 700mA level. However this seems to be out of stock in most places. The AB model has a pair of wires to control the "3-in-1" dimming function. You can use a 0-10V DC signal, a PWM signal or use a potentiometer (probably the safer bet). The AB model seems to be fairly available at the moment.

0.75A at 120V equates to a 160R resistor, which you could use to set up the driver and test the current before connecting them to panels to avoid panel destroying mishaps.

I'd buy a single unit first just to test the concept, then buy another 10x @ $50.

It's a little tricky to find other suitable drivers with V/I characteristics, at a good price point, availability etc.

I also encourage you to check the datasheet for anything I might have missed.

Thanks John that's a lot of info to take in but I agree I need to split the panel and drive it with something else. If I can find a driver that I can adjust the current to 350ma and Voltage to around 110vdc that would be perfect. Are there such things out there where both variables are adjustable

I won't be able to run cabling to 2 panels in parallel easily but am happy to get a driver for each light now.

1 thing that I'm very confused is constant voltage vs constant current drivers. Wouldn't dialing in the voltage (around 110v) to a fixed 350ma driver be the answer? Or it's a unicorn driver for my spec?

If I use the 700ma CC driver per panel could I put a resistor in series with the 1 panel , if yes I'm too dumb to figure it out what size and wattage resistor would do it?
 

Offline John B

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Re: LED Battern lighting is making my video flicker
« Reply #37 on: June 07, 2023, 02:24:07 am »
Most of the drivers have a combination of CC and CV control on the output. Meaning they will increase the output voltage until the maximum set current is reached through the load, or the max set  voltage is reached.

Connecting a 700mA constant current driver to a single panel would be a very bad idea. The linked driver could potentially output up to 142V, so it will raise the output voltage until it pushes 700mA through the single panel, probably destroying it in seconds. Adding a resistance isn't a solution since the driver will try to increase the output voltage to try and reach the 700mA target, it will only limited once it reaches the 142V max output voltage. But now the resistor will be dropping around 22V at 0.7A which gives you 15W dissipation in the resistor.

When you use a CC driver on 2 panels in parallel, the 700mA will be shared between the 2 panels, but the exact ratio is a little tricky since LEDs are non linear and the forward voltage lowers with an increase in temperature. Adding a small amount of resistance to each helps to match the ratio of currents, without dissipating too much power in the resistors. There is the potential to destroy a light if one goes open circuit, the full 700mA will be forced through the other light, destroying it. This is where an additional CV adjustment pot is ideal since you can set the max voltage to just above the voltage needed for CC operation. Alas the linked driver doesn't have it, only lower voltage ones do in the 24-54V range.

The driver could potentially work on a single panel if the dimming control was set to around 35% of its 1A output capability, but if you look at the datasheet, that is slightly outside the recommended I/V operating area. You'd need to ensure it starts in a failsafe way, ie the dimming control always works when the driver is on (like a simple potentiometer)

A 350mA driver for each panel would be ideal, but you need to find one that is capable of outputting up to 120V. I didn't see any suitable options, though something might be out there. Also even if you find something within those specs, they might have higher ripple anyways, bringing you back to square one.

You don't stand to lose much by buying a single test unit
 

Offline Automate007Topic starter

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Re: LED Battern lighting is making my video flicker
« Reply #38 on: June 07, 2023, 07:45:26 am »
A 350mA driver for each panel would be ideal, but you need to find one that is capable of outputting up to 120V. I didn't see any suitable options, though something might be out there. Also even if you find something within those specs, they might have higher ripple anyways, bringing you back to square one.

John you've been amazing with your knowledge and help Thank you once again . OK I think if you can look at the spec of this it might be the unicorn I have been looking for .... It's 42W, Constant current setting of 350mA and 110V, I know it might be slightly dimmer than the stock 45W driver but I don't think a loss of 3 watts will make a difference.

Could you take a look at the spec and let me know if I'm getting excited for nothing or it's worth a shot. I couldn't see anywhere regarding ripple voltage. https://www.meanwellaustralia.com.au/products/lcm-40
 

Offline John B

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Re: LED Battern lighting is making my video flicker
« Reply #39 on: June 07, 2023, 10:06:10 pm »
You said you measured 380mA at 120V DC, whereas the driver you linked has a maximum output of 100V when operating at 350mA. Open circuit voltage is 110V, so I would expect the panel to light extremely dimly or not at all. When I did a search on element14, mouser, and digikey I was looking for a max output voltage of >120V.
 

Offline Automate007Topic starter

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Re: LED Battern lighting is making my video flicker
« Reply #40 on: June 08, 2023, 02:13:25 pm »
You said you measured 380mA at 120V DC, whereas the driver you linked has a maximum output of 100V when operating at 350mA. Open circuit voltage is 110V, so I would expect the panel to light extremely dimly or not at all. When I did a search on element14, mouser, and digikey I was looking for a max output voltage of >120V.

Hmmm. I ordered 1 for testing. After I ordered I realised it has a 5% current ripple. So I guess that was a waste of money. Anyway curios to see what it does anyway.

I'm thinking maybe replace the lights with a high CRI >90 zero flicker free T8 tubes but hard to find at a decent price
 

Offline Automate007Topic starter

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Re: LED Battern lighting is making my video flicker
« Reply #41 on: June 10, 2023, 12:36:37 am »
You said you measured 380mA at 120V DC, whereas the driver you linked has a maximum output of 100V when operating at 350mA. Open circuit voltage is 110V, so I would expect the panel to light extremely dimly or not at all. When I did a search on element14, mouser, and digikey I was looking for a max output voltage of >120V.

Hey John, You are 100% correct. it arrived late afternoon. I hooked it up this morning

I thought I'd sacrifice the warm LED's if it went wrong! Just like you said it was very dim (around 1Watt) the unit was setup for 350mA on the dipswitches.

Result output was a very dim light and 100Vdc and only 10mA getting to the LED'S. So I don't get it...... if its supposed to be a constant current why is it not 350mA at 100Vdc?

I have to go away next week for work but in the meantime I found this one and am pulling all my strings to be able to get one to test with when I get back and the specs say </= 3% ripple current which seems to be the best I have seen so far.

https://www.tci.it/prodotti/alimentatori-led/968/mp-50-350-slim/
 

Offline Automate007Topic starter

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Re: LED Battern lighting is making my video flicker
« Reply #42 on: June 10, 2023, 12:42:59 am »
Datasheet
 

Offline John B

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Re: LED Battern lighting is making my video flicker
« Reply #43 on: June 10, 2023, 01:29:53 am »
Result output was a very dim light and 100Vdc and only 10mA getting to the LED'S. So I don't get it...... if its supposed to be a constant current why is it not 350mA at 100Vdc?

Most of the drivers have a combination of CC and CV control on the output. Meaning they will increase the output voltage until the maximum set current is reached through the load, or the max set  voltage is reached.

A real constant current device can only work within the constraints given by the load. You can test this idea with a couple of resistors. If you were to attach a 10R resistor to the driver, the theoretical figures would be given by ohms law: IR=V, or 0.35A * 10R = 3.5V. This is within the specified range of output voltages at 350mA, which is 2 - 100V. Also note that the resistor here is only dissipating around 1.2W and so isn't stressing the driver either.

On the other hand if you were to attach a 10 Megaohm resistor, an unlimited CC device would theoretically output 3.5 million volts to put 350mA through the resistor. Obviously this is not a realistic device. The driver in practice will only be able to increase the output voltage to around ~110V max as per the datasheet.

Likewise your panels have a conduction characteristic where they will only pass significant current once it reaches around the 120V mark. The conduction is gradual though, as you've found they will pass a few mA under the nominal operating voltage.

I would still stay with my recommendation of paralleling the panels in groups of 2. This is so that you only need to buy 10 drivers and not sink too much money into this system. Those LCM drivers still aren't any cheaper.
 

Offline Automate007Topic starter

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Re: LED Battern lighting is making my video flicker
« Reply #44 on: June 10, 2023, 02:21:18 am »
I understand you now. Makes total sense. The LED haven't overcome their forward voltage and therefore not sucking the max current yet till the voltage goes higher in which it can't get over the 100V!

I have a 40V 40W very good panel I tested a while back with CRI over 90. Testing with the driver it came with and flickers so given it was twice the price at $160 each I gave up on them . I figured I can try that meanwell driver I just got on it and it's freaking perfect. A 1V ripple and even with slow motion there is no flicker. But will mean around $160 per light plus the $75 meanwell driver I just tested it with
 and a load more holes in the gyprock to mount it but at least I know I have a way out of this mess ..... just a very expensive fix If that TCI 50W driver that I get next week doesn't work also he told me BTW around $30 each (hopefully he was not pulling figures out of the air) as they buy bulk but he wasn't sure if they had many left till next shipment and needs the warehouse manager to find them next week. So for now I wait!

 

Offline Automate007Topic starter

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Re: LED Battern lighting is making my video flicker
« Reply #45 on: June 11, 2023, 07:57:20 am »
Result output was a very dim light and 100Vdc and only 10mA getting to the LED'S. So I don't get it...... if its supposed to be a constant current why is it not 350mA at 100Vdc?

I got bored and decided I would sacrifice 1 panel in experimenting. I bridged 1 led and 8 in a group turned off but the rest lit up drawing 100ma. I then bridged another in the next group and went up even more. So I kept bridging groups till I got to 350ma and tge brightness was on slightly less than a fully lit panel using a light meter. Zero Flicker and driving with the meanwell LCM-40.

It's a cheap and nasty way and so far the easiest solution if all else fails!
 

Offline Automate007Topic starter

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Re: LED Battern lighting is making my video flicker
« Reply #46 on: June 11, 2023, 08:07:03 am »
So gone from 320leds to 272. 15% loss. So from 45W to 38W. I can live with that considering I have 8 of these in a 25mtr sq room! I really hope the other driver from TCI works as I feel bad screwing with LED panels like this! Also please ignore the quick n dirty solder.... I Know I know I'm cleaning it all up now once my vision comes back from staring at these LED'S head on
 

Offline Automate007Topic starter

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Re: LED Battern lighting is making my video flicker
« Reply #47 on: June 17, 2023, 01:41:23 am »
There's one last option.....

The last option of re working the light and adding that 50W TCI LED Driver turned out to be the best option. Worked perfectly and I have completed the conversion of 8 lights in 1 room. Zero flicker now. Thanks mate for all your help getting me through this hurdle. I tried to make it as clean and safe as possible . Even added labels everywhere on the light under the covers indicating 120VDC so at least in the future if anyone buys this premises can clearly see its not 240Vac and being driven by a LED driver
 

Offline Automate007Topic starter

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Re: LED Battern lighting is making my video flicker
« Reply #48 on: June 17, 2023, 01:45:47 am »
Here are some pics of what I did to modify and label
 

Offline Automate007Topic starter

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Re: LED Battern lighting is making my video flicker
« Reply #49 on: June 17, 2023, 01:48:18 am »
Some more
 

Offline John B

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Re: LED Battern lighting is making my video flicker
« Reply #50 on: June 17, 2023, 02:11:25 am »
Looks pretty safe, however I'd never leave these types of things behind when moving out, or at the very least it doesn't contribute to the value of the property since it's probably not an """approved""" install. Just to cover your own backside.
 


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