Hello my favorite forum.

(Dave Morris) #1

Hello my favorite forum. I recently finished up cove lighting project consisting a single line of 3 x 5m ws2812 lights @ 30 pixels/m.

A 24v, 4A supply powers a bus wire along the way to power 4 x DC-DC converters rated for 5A max installed at each strip termination so no more than 2.5m between 5V injection. I consider that pretty generous power which is by design after I fried everything on my previous 2 converter setup after 30 seconds of all white @ 40% brightness (didn’t think I needed to adjust maxCurrent at such a dim brightness… Was wrong)

With 20 amps max of evenly spaced 5V power (and maxCurrent set to 15 amps now :+1:)… my converters get really hot at seemingly low loads. Rainbow @ 150 brightness for a few minutes makes the heat sinks too hot to touch for more than a second so I’m running much dimmer. The 2 step downs at each end of the set are noticeably cooler then the two inline but still pretty warm. All injection points measure at 4.9 to 5.1 volts.

I’m seeing other such linear projects with substantially less power considerations working just fine. So are they cranked way down on brightness or is there something I did wrong with my converters/placement. My theory is the converters are somehow fighting each other? Maybe the difference between 24v down to 5v is the cause?

Here are the converters I’m using adjusted to 5v outout

[4-PACK] 5A DC-DC Adjustable Buck Converter 4~38v to 1.25-36v Step Down Power Supply High Efficiency Voltage Regulator Module ([4-pack] 5a buck) https://www.amazon.com/dp/B079N9BFZC/ref=cm_sw_r_cp_apa_qHC.BbA0643VC

(Gibbedy G) #2

Do they all get hot hot?
I’m guessing overtemp/overcurrent protection didn’t work on either of your first two converters regardless of any wiring fault.

(Marc MERLIN) #3

Try adding some inline amp meters to measure the amps at each point

(Mark Sanders) #4

As far as I know it is against best practices to use more than one power supply in the same power rail. Could you try to segment the 5V rail of the LED strip into separate parts and power each one with one DC-DC converter?