[SOLVED] ATX 300W power supply in problem

[demetal]

Hi i have an old ATX power supply of 300W a product by frontech (model- ATX P4 POWER SUPPLY JIL-2406 ).... i found that its three resisters just burned out (i dont have the resistance value) and a capacitor (1000uF 10V )which got exploded ... Now the power supply is not working...I want to recycle it to use for a HHo cell power supply.... When i removed the resisters (burned) and the capacitor along with the adjacent heating capacitors and switch it On without replacing the components i removed the power supply is working but producing heat and a noise sound in the three transistors connected to the heat zinc as shown in the image below....

**broken link removed**

Can any one help me to repair it....

 

[amu_cpln]

the noise is probably from your transformer, the absence of capacitor now cause some current spikes in the transformer
adding some filtering at output will help
capacitor value is not very critical ..
anything in range 470uf to 2200uf

 

[dselec]

U will need to draw the circuit yourself showing the 2 resistor layout and cap u may have the problem in low volt side easier to repair. google has a lot of circuits try to find out similar to yours
https://www.google.co.il/search?hl=...0.16.0.0.229.1015.1j4j1.6.0...0.0.MS8xpdNHKFg

 

[demetal]

Hi,

Here is the circuit diagram of the power supply i had and the problems are explained and noted in the diagram



Is there any way to repair it.....

also i want the reason for these burning out of resisters and explosion of the capacitor and the heating of that part of heat zinc when i removed these capacitors and resistors from circuit without replacing it with other ..

please help....

 

[tpetar]

What is status of D7 and D9 diodes?

---------- Post added at 23:38 ---------- Previous post was at 23:33 ----------

C15 and C18 cap is black with white/silver color or blue with gold ?

---------- Post added at 23:44 ---------- Previous post was at 23:38 ----------

What is their temp value 85C or 105C?

What is status of fan of PSU ? Maybe fan have malfunction and overheating of cap occur and then starts chained fireshow with resistors and others parts.

 

[demetal]

d7 and d9 are looking good externally(i.e; not burned).... the capacitors are black with golden colour...

---------- Post added at 03:15 ---------- Previous post was at 03:14 ----------

Does this capacitors differ from ordinary capacitors....?

 

[tpetar]

Cap is dark blue or black ? and color for minus is like bronze ?

Check with unimer diodes in both direction if possible, or replace them.


Cap is colored like this big in up middle ?

 

[demetal]

The temperature is getting increasing when the mains is connected... also the fan is not working at initial state after sometimes the fan starts running with a noice... and the output starts appearing ...instead of 12 V its showing 10 V and also the U2 starts heating...(this is in the case of removed capacitors and resisters i didnt replaced them with other...)

---------- Post added at 03:23 ---------- Previous post was at 03:19 ----------

Cap is dark blue or black ? and color for minus is like bronze ?

Check with unimer diodes in both direction if possible, or replace them.


Cap is colored like this big in up middle ?

Yes ..Its Black with Bronze colour for 1000uf... and i dont remember about other as they got exploded....

The 1000uf capacitor was bulged and over heated and exploded...

Can you explain the Unimer diode connection you have described...

 

[tpetar]

The temperature is getting increasing when the mains is connected... also the fan is not working at initial state after sometimes the fan starts running with a noice... and the output starts appearing ...instead of 12 V its showing 10 V and also the U2 starts heating...(this is in the case of removed capacitors and resisters i didnt replaced them with other...)

Uuuuuu my friend You play with fire.

If cap is dark blue/bronze (gold) then this is low ESR cap. Buy new withhigher voltage retings. Changde diodes, change resistors, change fan, assemble all in case and test it.

My advice this is very cheap device one of Chinese miracle in electronics, they made this for 4-5usd, I dont know how.
Buy new its my advice.

Avoid this situations:
https://www.youtube.com/watch?v=3MMZMzReueQ

 

[demetal]

Actually this is not for my computer as i have brought a new one,.... You know in previous forum about HHO power supply... i decided to recycle this for that application so for that only i am stick on it.....

For this i need suggestions from experts like you...

I have a question... do i need to check all those diodes or just the D7 and D9....?
Can i replace those capacitors with the general purpose capacitor.....?
What makes the ordinary capacitor differ from these type....?

Or

Is there any method to extract the 12 V supply with 10 Amp from this circuit..... no need for SMPS and all stuff...?

 

[tpetar]

Does this capacitors differ from ordinary capacitors....?

Of course my friend its low ESR cap, price is also different. ;-)

Buy it same cap 105C temp ratings and for double voltage from original if they have in market store. I think you have enough space to built in them.

You can dissasemble this cap from some motherboards, but watch that they are ok. They are placed around CPU socket.

---------- Post added at 00:08 ---------- Previous post was at 00:04 ----------

Is there any method to extract the 12 V supply with 10 Amp from this circuit..... no need for SMPS and all stuff...?

In this injured condition I dont think so that this PSU is ready for fight with some loads.

 

[demetal]

Ok fine, Can you please tell me whats actually happened... the reason which made these firing of resisters and the explosion of capacitors.... A am asking to know the technical failure which had occurred here....

 

[tpetar]

Low ESR Capacitors - Equivalent Series Resistance

**broken link removed**

Links :

**broken link removed**

https://www.illinoiscapacitor.com/pdf/Papers/low_ESR_fact_or_fiction.pdf

https://en.wikipedia.org/wiki/Equivalent_series_resistance

**broken link removed**

 

[demetal]

Can you please explain me the technical failure reason of this system....

---------- Post added at 03:53 ---------- Previous post was at 03:51 ----------

Actully... first the resisters burned... then after that when i removed the resisters and switch on the mains the capacitor bowed....:roll:

 

[tpetar]

I lost my last post, I dont know how this happen.

---------- Post added at 00:28 ---------- Previous post was at 00:26 ----------

Again,




Fan is stoped, or slowdowned, temp increased and cap exploded, fireshow continue on resistors and other parts.

Diodes D7 and D9, one of them or both damaged.

T3 have bad day.

 

[demetal]

Ya i saw it first... now its missing...

---------- Post added at 04:01 ---------- Previous post was at 03:59 ----------

So the AC coming from the transformer is making the capacitor charge in AC... Is it the reason behind the over heating....?

 

[tpetar]

My pc working for 5 PCs. It have 1KW PSU and carring video survailance, 1-wire monitoring os tons of sensors and alarms,... plus other regular things. Maybe I click on something wrong or he celebrating 01.may.

 

[demetal]

So is the T3 alive or dead....?

 

[tpetar]

I dont know that, maybe there is breakdown of coils. This trafos dont tolerate higher temp like other parts, because fans is very important to be functional with full capacity.

 

[demetal]

Ok let me check it... I dont have stock of low ESR capacitors so today morning i have to get them... lets check whether it works or not...

Also do we need to replace the resisters and diodes by the exact one or by any general purpose one like carbon1/4 w resisters and diodes like 1N4007...?

Also i want to know that is the damage of resisters and capacitors is making a heating effect in the transistor T3... Or is there any other possible reasons for that...?

Thank of the last reply's..