Here's the situation: I bought some cheap LED pot lights off of Amazon to use in a project. These pot lights take 120VAC input, run it through a rectifier, and output 5VDC or 34VDC (depending on the temperature selection). I have some wireless LED dimmers that pass DC input, and I had a cheap 24V 10A DC power supply handy (again, from Amazon), so I supplied DC input to the pot lights, and they worked! They weren't totally bright, but for the project, they would suffice.

Recently, I decided to switch out the cheap power supply for an Meanwell 24V 15A power supply (Model #LRS-350-24). The circuit itself remained unchanged, but now the pot lights won't turn on, and I cannot figure out why. I'm getting +24VDC input into the rectifier, but no dice. Just to be sure, I went ahead and provided a 120VAC input to one of the lights, and the light works as expected.

Why is the cheap power supply working in this case, but not the Meanwell?

Below is an image of the board for powering the pot light:

Pot light circuit board

  • \$\begingroup\$ reverse polarity perhaps? \$\endgroup\$
    – jsotola
    Dec 10, 2022 at 5:45
  • 1
    \$\begingroup\$ cheap LED pot lights […] output 5VDC or 34VDC I'd expect them to output light. Where does the DC appear, what is it used for? The range is pretty wide. \$\endgroup\$
    – greybeard
    Dec 10, 2022 at 6:30

1 Answer 1


The first power supply's voltage was set to 32 volts - I changed it and forgot, so I assumed it was the original 24V. Upping the voltage on the Meanwell fixed the issue.


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