LED Power Supply Dimming

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  #1  
Old 01-06-14, 06:27 PM
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LED Power Supply Dimming

Have a 60VA DC power supply that can be dimmed if loaded to level close to its rating of 60VA per mfg instructions. If the supply is not loaded the LED's flicker when the supply is dimmed.
I do not have enough LED's to reach the loading the mfg says I need. My question is, has anyone had success installing a resistor across the power supply secondary to increase the loading to smooth out the dimming? They don't have a smaller power supply so I am stuck with the 60VA.
 
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Old 01-06-14, 09:21 PM
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I've never tried it but it makes sense.
I was wondering what if you used like a [email protected] capacitor.
 
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Old 01-07-14, 10:47 AM
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LED Power Supply Dimming

Thanks for the reply, hadn't thought of a capacitor. Not sure of all the theory behind just why the supply needs to be loaded in order to dim properly, but would like to be able to do so. Thanks again.
 
  #4  
Old 01-07-14, 12:45 PM
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Is the power supply built for LED driving? If so, I would guess it uses pulse width modulation (PWM) to dim the LEDs. A capacitor would defeat PWM. The resistor would work but you will need a very high power resistor and maybe a fan to keep the heat off it.
 
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