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Teardown of a "24V 4A" power adapter

W

wwenze

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The sheer extent of absurdity compels me to reveal its innards before disposal. This weighs less than a proper 5V 1A USB charger. "24V 4A" lol.

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8.2uF 400V capacitor totally screams "96W power supply"

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A single SS215 for secondary side. 2A forward current. Probably never sees that much.
No optocoupler.
MB10F for rectifying mains AC, 0.8A
And those output wires scream "Hey I can carry 4A... while burning your house down"
 
wwenze said:
The sheer extent of absurdity compels me to reveal its innards before disposal. This weighs less than a proper 5V 1A USB charger. "24V 4A" lol.

View attachment 498363View attachment 498364

View attachment 498365
8.2uF 400V capacitor totally screams "96W power supply"

View attachment 498366

A single SS215 for secondary side. 2A forward current. Probably never sees that much.
No optocoupler.
MB10F for rectifying mains AC, 0.8A
And those output wires scream "Hey I can carry 4A... while burning your house down"
Click to expand...
That's a really cheap construction. I don't think it would pass any of the official stress tests.

The CE mark looks fake.
Is the middle line in the E exactly flush with the top and bottom lines, or is it set back?
 
Roland68 said:
The CE mark looks fake. Is the middle line in the E exactly flush with the top and bottom lines, or is it set back?
Click to expand...
Yes, you are right, it's a bit wonky! It's not the one with the CE closer together, generally incorrectly called "China Export". There is no such thing as a China Export mark ;)

In this case, it looks like they just cut the end off the E. A stupid copy/paste issue, or similar. The FCC logo looks alright at least.
 
two questions for the OP.
1) What was the provenance of this wall wart? Did you buy it, did it come with something you bought, or did you find it by the side of the road?
2) Irrespective of its nominal current rating, does it in fact output 24 VDC into any load (or with no load, for that matter)?
 
voodooless said:
Yes, you are right, it's a bit wonky! It's not the one with the CE closer together, generally incorrectly called "China Export". There is no such thing as a China Export mark ;)

In this case, it looks like they just cut the end off the E. A stupid copy/paste issue, or similar. The FCC logo looks alright at least.
Click to expand...
mhardy6647 said:
two questions for the OP.
1) What was the provenance of this wall wart? Did you buy it, did it come with something you bought, or did you find it by the side of the road?
2) Irrespective of its nominal current rating, does it in fact output 24 VDC into any load (or with no load, for that matter)?
Click to expand...
With power supplies like these, I always consider it a bad sign when the actual manufacturer doesn't dare to put their company name on them.
 
unmutual said:
With power supplies like these, who needs enemies!
Click to expand...
But you could give them to your enemy as a gift, following the motto: be close to your friends, but even closer to your enemies ;).
 
mhardy6647 said:
two questions for the OP.
1) What was the provenance of this wall wart? Did you buy it, did it come with something you bought, or did you find it by the side of the road?
2) Irrespective of its nominal current rating, does it in fact output 24 VDC into any load (or with no load, for that matter)?
Click to expand...
1) It happened to be inside "The Box"
2) I wasn't comfortable enough to plug it into mains. Worst case given the weight it could have been a capacitor-divider type power supply and I'm not touching my multimeter to that.

Probably came from some taobao product bought by my mom. They make every type of product imaginable. I dealt with a lotus lamp that ran on 3.3V that came with a USB charger that output 3.3V, which was working intermittently on arrival so I had to update the product to use 5V USB via a linear reg. The religious creates problems and ask for the science to solve, *shrug*
 
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This would have been a much more interesting thread if you had put it on a test bench and actually pulled 96W from it to see what happens. ;)
 
I say, hook it up, draw the claimed current out of it, equip yourself with a beer, and laugh as it starts to smoke.
 
Cautious assumption: It will deliver the rated power.
For a few seconds :)
 
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