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I am trying to finish the LED dimmer project using white LEDs 5054 DC12V (240 LEDs) on aluminum plate and diffusor plate. I have burnt out couple of potentiometer and resistors trying to control the brightness.

Here is what I have calculated

White LEDs Strip 5054 DC12V

24 LEDs x 10 strips = 240 LEDs

8 x 56 ohm per strip = 448 ohms per strip
10 strip x 448 ohms = 4480 ohms

24 x 60 mA = 1440
24 x 3.4 V = 81.6 V x 10 = 816
24 x 1 W = 24 W x 10 = 240 W

Formula Amps

240 W / 12 V = 20 amp

Can anyone help me put together the correct component to control the brightness of the LEDs?

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    \$\begingroup\$ A potentiometer, that can control the brightness of this LED array and survive it, has a weight of around 2.6 kg. This is not an acceptable solution, except you want an illuminated toaster. In my estimation this array consumes around 60 W, the calculations are wrong. The resistors are not in series and cannot simply be added. Some LEDs are in series and so the currents cannot be added. To correct this, a datasheet of the used LED strip is required. \$\endgroup\$
    – Jens
    Sep 14, 2023 at 23:09

2 Answers 2

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If those are 60 mA per diode you're closer to 5A/60w. That is too much for a potentiometer (at least without spending a lot for a massive one).

A better solution would be to get a PWM dimmer that rapidly blinks the lights on and off. You could make one easily enough, or buy one for a few dollars online.

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You can use the potentiometer to control a PWM driver to control the brightness: enter image description here

A transistor or other power switch is required to be able to carry enough current. This illustrates the schematic, but Q1 needs to be changed to a transistor with 20+ A current rating: enter image description here

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