QJE 15V 30A Adj Switch mode Power supply! Surprise parts inside

[junggwok]

I bought this cheap power supply when I was China last week. Because I need high power supply for my audio amp project, my Array 3645A Programmable (3A) power supply just cannot supply enough current or my 5Amp Manson linear supply. I thought I open it and see what's inside. I actually quite by the parts used inside. Two massive Rubycon 200v 680uF Electrolytic Capacitors. I thought really, because I only paid $55 Australian dollars for this, granted the voltage is only adjustable from 9v to 15v but that's all I needed. I actually managed to trim it down to 6v, simply hack, now the supply is adjustable from 5.9V to 15.3V. Will test the 30A power rating with my electronic load. I will let you guys know how it performs under full load.

[bingo600]

Lets not hope that,the PSU was to cheap  .....
https://www.eevblog.com/forum/projects-designs-and-technical-stuff/warning-fake-large-electrolytic-on-ebay-!!/   

/Bingo

[mariush]

Even if they were real, the last accepted order for that series was in September 1999.  USP is a discontinued series, 85C standard, not 105c as the label says, so it's probably fake.

See page 9 on their document: http://www.rubycon.co.jp/de/catalog/e_pdfs/aluminum/CautionAlumi_Eng.pdf

ps. check the voltage rating of that small capacitor by the banana jacks... if it's 16v replace it with a 25v one at least, 15v max voltage is awful  close to 16v and you don't know how much ripple this will do.

I doubt it can do 30 A, it will probably burn up at 10-12A, and the cables don't seem thick enough to do 30A.

ps2. bingo probably wanted to link to this page, his link is bad:  https://www.eevblog.com/forum/projects-designs-and-technical-stuff/warning-fake-large-electrolytic-on-ebay-!!/45/

[robrenz]

Scroll way down on this page to figure 38 and 39 to see what is in some caps.  I hope this is not what is in yours. if you have a capacitance meter it would be interesting to see what the capacitance is.

http://www.turtlesarehere.com/html/cd_welder.html

[T4P]

Don't forget ESR. The most important thing

[Rerouter]

the fact it was reading so low, as stupid as it sounds, where where you measuring the voltage? at 30A your talking serious voltage drops even if only from the pcb to the front connectors,