MPJA 10 AMP @ 0 to 30 Volts Switching Power Supply Cap Fault

[sam_sam_sam]

I have this 10 amp 0 to 30 volt switching power supply that decided to have a 630 milliamperes draw on it at 0 volts

I open it up to find non brands name capacitors in it

I am not sure how this switching power supply is set up

Could someone please explain how this power supply works

Here is the capacitor ESR results

(1) 47uf@50 volts 0.46
(2) 47uf@50 volts 0.45
New 47uf@50 volts 0.35

(1) 100uf@25 volts 0.34
(2) 100uf@25 volts 0.35
New 120uf@50 volts 0.08

(1) 220@25 volts 0.13
(2) 220@25 volts 0.13
New 220@35 volts 0.03

(1) 1000@35 volts 0.03
(2) 1000@35 volts 0.03
New 1000@35 volts 0.02

3300uf@35 volts 0.02
New 3300@35 volts 0.02

[stj]

Re: MPJA 10 AMP @ 0 to 30 Volts Switching Power Supply Cap Fault

interesting.
see the current shunt coil?
it connects to the small board - i suspect the 2 ends feed an op-amp to monitor the voltage drop.

btw, the internal tactile switch is just asking to be pressed!! they should have painted it red!

[sam_sam_sam]

Re: MPJA 10 AMP @ 0 to 30 Volts Switching Power Supply Cap Fault

Yes
I wonder about that button as well just what does it do

The button does not seem to do anything at all but there is another connector that might be how you program the controller but this is only a guess

On the small board the small IC chip is a LM 358

The switching power supply is back working again
The only problem this power supply has is that it has to be ON a little while for the voltage to stabilize it drift a little bit a couple hundredth of a volt for first 5 minuets or so and then it fine

But it has done this when I first turn ON new out of the box

[sam_sam_sam]

Re: MPJA 10 AMP @ 0 to 30 Volts Switching Power Supply Cap Fault

I used the following caps
KY
KZE —> maybe
LXZ