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Removing one strip of LEDs from panel

My LED panel broke (it is a ceiling lamp).
I disassembled it, and it looks like this:

LED panel

It has a series of LED strips (the last one is missing in the image), connected in series. There are connectors like the one on the left in the picture between strips; the last connector is just a closed loop of wire, and the first strip is attached to the transformer:

enter image description here

By testing individual strips, I discovered that one of them is broken (some of its LEDs look damaged, with a black dot in the center). With all the strips, the panel doesn’t work when attached to AC.

I’d like to repair it, I’d be fine with one less strip (since I can’t find a replacement online).


  1. If I remove the broken strip, should I expect the others to break? I’m confused by what I read on the transformer label, it says "Output: 30-39V". Why is there a delta? Is the transformer/driver able to regulate the voltage/current depending on what is connected to it?

  2. If the answer to 1 is "yes", is there something I can do to avoid it?

  3. Bonus question: as you may see in the first image, there are arrows on the strips, reading "+/-" on the right, and "+/+" on the left. They were mounted like this:

← this one failed


I this it doesn’t make sense, I would have expected either all the same direction, or alternating ones. Does it make a difference?

I apologize for my scarce knowledge of electronics if the question is trivial, my local repair shop did not even want to see the LEDs and I wanted to try some DIY.

Thank you.

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