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Old 11-07-2019, 09:18 PM   #25 (permalink)
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I got the ac-dc power supplies tonight. They're larger than I thought they'd be at about 5.25" long. However they are very light weight. I'm thinking I may take them out of the cases when I get to putting everything together. It will be better for cooling and size.

Here is the specs on it. It actually puts out about 12.3V which is fine for this purpose.

So, I hooked up one of the power supplies to the dc-dc converter. Then, I hooked the dc-dc converter up to the multimeter set to measure amperage and let it run for a while.

I wanted to see how hot the dc-dc converter would get just running at 4A for a while. It turns out, it runs pretty darn hot. I'm definitely sure I don't want to run it at 5A. The diode (the thing just to the right of the inductor coil) gets very hot. I measured the best I could with my IR temp gun and the highest reading I got was 216F after a few minutes running. The chip says SK54 on it, so I googled that. The first data sheet I found says max junction temperature is 300F. The capacitors were also pretty darn warm at ~145. A quick google search says electrolytic capacitors are good to about 180F. So, I guess I'm okay? Electronics guys feel free to jump in with some feedback.

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