pup30-25 power supply

[Doug]

the name on it is international power source doing web search and ebay searches pup series has the names Power Box,Tumber technologies, trump power...its a switch mode supply output 5v 3a and 24v 1 amp..everything on the board lookgood caps no swelling,leaking,nothing burnt..driver transistor has 160vdc on it.Primary side only has two caps filter and possible drive.. i tried replacing the drive which was a 47uf 50v no change..dont find anything shorted on the secondary side.no noise when power up.Anyone know were i might get more info on this guy?
Thanks

 

[panic mode]

do you have picture?

SMPS with dual caps are usually universal input PSUs (can operate on either 15 or 230VAC input), in which case rectfier stage looks like this:
https://www.repairfaq.org/sam/smpsvs.gif

to operate properly, such PSU must be configured. when it ofrom 115V, jumper (or switch) must be closed and then stage works as a voltage doubler (DC bus is 2*160=320VDC). obviously jumper or switch must be off when PSU is powered from 230VAC or PSU will be destroyed.

if the bus voltage is not right, chopper may not even oscillate and in that case you get no output.

 

[dougy83]

So what is the actual problem? It won't start up, or that you want it to make noise?

If you have a look at the datasheet, the PUP30-25 has a minimum output current specification - so try connecting it to a load and it might run. I assume that by 'drive cap' you mean the bulk capacitor and that the 'filter caps' are just small-valued caps after the common-mode choke.

There may be a fuse (or an NTC or resistor) in line with the primary that has gone open-circuit as well.

to operate properly, such PSU must be configured. when it ofrom 115V, jumper (or switch) must be closed and then stage works as a voltage doubler (DC bus is 2*160=320VDC). obviously jumper or switch must be off when PSU is powered from 230VAC or PSU will be destroyed.

if the bus voltage is not right, chopper may not even oscillate and in that case you get no output.

From what the OP stated (https://www.electro-tech-online.com/custompdfs/2012/10/pup30.pdf), the SMPS is a universal input PSU; there's no need to "configure" it.

 

[Doug]

Thanks for the responces.yes a picture would help. I will get it posted later.I dont have this a home.In consumer electronics there was a very low value cap usually BP that would be weak. The cap I was refering to is in the bias of the driver transistor.I did a little more checking there is two resistors 10k 2-3w that feeds a vertical board with 2 8 pin ICs and a 1.5meg 1/2 watt resistor that feed the same board .both of these feed from the 160v primary voltage . Both resistors are good. The vertical board is too close to the heat sink I'll have to remove it to get the IC #s.Maybe from there I can get data on the ic sometimes the show sample circuits which will give me some road map..
Thanks
Any more ideas appreciated..
no output at all..I'll load it and check for jumpers Monday..as the noise sometimes they squeel or chirp when having problems ..this one is just quite..

 

[Doug]

Also the 2 ICs I believe one is for the driver and the other is for feedback regulation

 

[Doug]

Today I hook up an external power supply to B+ primary supply ( 20v only supply on hand)and a variable supply to 10k resistor that feeds the little vertical board . Brought the supply to the up to 16v and unit started working. remove the 16v supply and unit still ran. 5v and 24v on the outputs.tested again on 120vac nothing...
the little verticle board has three pins seperate from the other 5 pins. These three pins are close to the secondary side which is the monitor for shutdown. Scoped all three pins for spikes and DC on turnon..nothing...removed small verticale board..removed conductive dried glue..reinstalled ..everything works...conductive aged glue strikes again.
FYI the ics were KA3842a SMPS driver, LTV702 optic isolator