Electronics > Repair
Please help power supply dead 110V to 24vdc 5vdc
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kripton2035:
repairing methodology for smps.
https://www.repairfaq.org/sam/smpsfaq.htm
as noted above, please be aware that these voltages can kill you !

I also very doubt of only 24V dc on the 150uF 400v capacitor : it should be around 150V DC for a 110v mains supply.
Miti:

--- Quote from: RomDump on February 21, 2020, 04:26:39 am ---With some googling U1 appears to be FA5501AP, (I have attached the Datasheet)....
The datasheet has an example circuit which resembles the first half of your circuit.

--- End quote ---

I doubt, that chip is a PFC controller. The chip is ID13301 apparently but I can't find a datasheet.
The fuse is FS1 and if that is good, start by replacing the three smaller capacitors in the primary, the 100uF first.
If the cap on the supply line of the controller goes bad, the chip can't start.
TheMG:
The blue component you identified as a "varistor", is in fact a capacitor, it's there for EMC reasons.

The component you identified as a MOSFET is simply a dual schottky diode in a TO-220 package. Very common to see these in SMPS. It's the secondary rectifier diode (note how the two outer pins are inter-connected, effectively paralleling the two internal diodes).

I think it would be wise to set this repair project aside for a bit and brush up on your electronics knowledge particularly when it comes to SMPS theory of operation and typical design characteristics.
Haenk:
You did notice, that it has an external on/off function, did you?
Just connecting the PCB to mains will not fire up the PSU - you will have to activate it via that on/off line. (to ground? to 24V? resistor to gound? - You should explore the connector, or maybe someone has an idea).
And as already said - this PSU could easily kill you. Even when it has been disconnected from mains before. Not kidding.
administr4tor:
hello, i measured more voltages, please have a look..

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