LED Strip lights flickering -

wreini

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Hoping for help to fix this. I have built a Square LED light panel with dimmers for photo shoots. I have a 150 W double output LED Driver : http://www.amazon.com/dp/B00HCXEBNU/?tag=cpf0b6-20 with (16) 18" strips of 5050 LED tape soldered together. They work fine at full power, but when I dim them, a flicker starts. Each supply line going to the LED strips has a dimmer: http://www.amazon.com/dp/B007V1B0W8/?tag=cpf0b6-20 Don't know if I put a capacitor or something in if I can stop the flicker. Any suggestions on how to eliminate the visible flicker?
 

wreini

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Nope, It is a PWM Dimmer Controller DC12V 8A 96W (link above to amazon).
 

FRITZHID

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How rapid is the flicker? Is it flicker or actual strobing (constant or random flashing)?
I'd guess that either you're putting to much of a load on the P.S.U. or the dimmer(s) OR your dimmers are PWMing at to low a freq and a higher quality faster PWM dimmer is in order.
 

electronupdate

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Any suggestions on how to eliminate the visible flicker?


The driver you have chosen is , by definition, going to produce flicker. PWM = pulse width modulation == turning the LEDs on-and-off with a specific duty cycle. As you have noticed most camera can see this... even increasing the PWM frequency does not solve the problem since you can get an alias or beat-frequency effect.

You want a "constant-current driver". This will probably not be a readily off-the-shelf item.
 
Last edited:
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Jul 15, 2007
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Your LED tape is using resistors to drop the 12V to the required Vin for the 3x LEDs in each pack. The dimmer is flickering the lights on and off very quickly to simulate lowering the brightness. It isn't working...

You *could* put a cap on there, but I don't think it would do much other than lower the effective voltages of the strip which defeats the PWM.

Strips aren't good choices as they can't really be run in CC mode.

Personally? Cut the strips so you can run 1,2,3,4 ... that'll give you the old style strobes of where you could have full power, half power, but not infinitely adjustable.

Also know that your lights may suffer from bad skin color due to low R9 on the CRI scale.

Good luck
 

SeanSVU

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I've run into this issue as well. Check the connections, make sure the end has a cap, and be sure you're using enough power through a transformer for the LED strip. Did you solder the connections? I checked the PSU you're using, it's 24v. are your strips also 24v? that could be the issue.
 

SeanSVU

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Disregard my soldering question. The problem is the PSU is not dimmable. LED PSU's are much different as you need a minimum current to be able to dim your LED's. Just search dimmable LED power supply on amazon and that should help.
 

trojansteel

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I have this issue too, kind of. I recently bought a house and the LEDs are in ceiling cans. They sometimes flicker when not at max brightness. Any easy fix?
 
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