M2 ATX chinese clone psu problem

R!f@@

Joined Apr 2, 2009
9,918
The dead battery cannot be done. The charger inside the batter was ashed.
But I was the lucky one. I ended up with these
 

Thread Starter

ViperRunner

Joined Jan 30, 2010
50
Yeah ;) now you have some cells to use on something ;)

I have 12 too heheh, 6 not so good from the old battery, and 6 good ones from the too old but still in very good condition m1330 battery i had around here!

and here are the pics!

The board on it's present condition:



And the little stupid and cheap meter i use to test capacitors :D:


regards
 

Thread Starter

ViperRunner

Joined Jan 30, 2010
50
To Spare some time, i will be putting here answers to the points 1, 2 and 3 in case it's still the same from this image:

1. The left side of this capacitor is connected to +B, ant the right side to -B

2. Has no contact, but one thing i noticed is that it has contact with the right side of the now missing fuse, so by logic to be in contact with B+ it has to have there a working fuse, i'm i thinking right? i take this theory because the left side of the now missing fuse makes contact with B+

I'm i thinking straight?


3. Is with contact to -B
 

R!f@@

Joined Apr 2, 2009
9,918
Ok.. here is the summary.
Looking at the last pic I posted.
1 shows track which is connected to the fuse and it is the incoming +B and through the fuse it goes to the rest of the circuit plus to the diode cathode too. This diodes anode is grounded. ( no. 3 denoted track ) Remember this...if the anode is connected to -B then, this diode is a 16V Zener or mainly for reverse battery connection protection. Either way you can replace it with a normal diode, but this being a DC to DC converter the input current is quite high, say may be around 25Amps for 300W PSU. In this case the fuse will be strong and if a battery connection reversal occurred the diode should have the capacity to blow the fuse.
For this reason the replacement diode must have the surge current capability of around 20 to 30Amps.
But on the other hand If you are careful then you won't need this diode.
You can bridge the broken fuse and replace the +B line with an inline fuse holder of around proper capacity.
what is left now is the burned component.
<internet go figure>
I'll be back
 

Thread Starter

ViperRunner

Joined Jan 30, 2010
50
Ok.. here is the summary.
Looking at the last pic I posted.
1 shows track which is connected to the fuse and it is the incoming +B and through the fuse it goes to the rest of the circuit plus to the diode cathode too. This diodes anode is grounded. ( no. 3 denoted track ) Remember this...if the anode is connected to -B then, this diode is a 16V Zener or mainly for reverse battery connection protection. Either way you can replace it with a normal diode, but this being a DC to DC converter the input current is quite high, say may be around 25Amps for 300W PSU. In this case the fuse will be strong and if a battery connection reversal occurred the diode should have the capacity to blow the fuse.
For this reason the replacement diode must have the surge current capability of around 20 to 30Amps.
But on the other hand If you are careful then you won't need this diode.
You can bridge the broken fuse and replace the +B line with an inline fuse holder of around proper capacity.
what is left now is the burned component.
<internet go figure>
I'll be back
This is a 160w psu, so a 20A fuse should be enough no? or maybe a 15A? And the diode, can't i get a diode for this amps in a motherboard or something? or else i think i have four 6A diodes somwhere, if i joint them they will make a total capacity of 24, that may be enought no? but together they will be about 1/4 of the size of the board heheh, but if needed to work, i will put them :D

and about the other two missing components: the one that burned, and the second smaller one that got off yesterday, they are both capacitors right? won't the circuit work without them? but offcourse that it's better if i can substitute them, but for that how will i find suitable substitutes on for example a motherboard? they are all the same to me hehehe they all look alike! :D
 
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R!f@@

Joined Apr 2, 2009
9,918
The burned component was a bypass capacitor and the one that came off also was the same thing.
Now when I think of it,what happened in the first place.
If you have checked the fuse before and if it was OK then you should not have a problem even though the bypass caps got burned. It will still work provided the PWM is working.
But the diagnosis shows a leaky diode, if so then the fuse will be open, but I cannot see any where that the fuse was checked before hand, am I right.
so, be that as it may. Your supply will be still functional if you bridge the fuse. I don't see any other reason it should not work. It's time to power up.
Leave the diode. Get an inline fuse holder and first use around 2A fuse, just give the 12V to ACC and +B. No load now.
If the fuse does not blow then check the outputs.
You should at least get the standby 5V
 

Thread Starter

ViperRunner

Joined Jan 30, 2010
50
The burned component was a bypass capacitor and the one that came off also was the same thing.
Now when I think of it,what happened in the first place.
If you have checked the fuse before and if it was OK then you should not have a problem even though the bypass caps got burned. It will still work provided the PWM is working.
But the diagnosis shows a leaky diode, if so then the fuse will be open, but I cannot see any where that the fuse was checked before hand, am I right.
so, be that as it may. Your supply will be still functional if you bridge the fuse. I don't see any other reason it should not work. It's time to power up.
Leave the diode. Get an inline fuse holder and first use around 2A fuse, just give the 12V to ACC and +B. No load now.
If the fuse does not blow then check the outputs.
You should at least get the standby 5V
I'm not completely sure, but i think that the fuse never had contact between it's two sides since we started all the testings.

Then should i leave the circuit without the diode for now?

and i have inline fuse holders but i'm affraid they won't fit there, the space is not as much as it may look for the images, i think that's why the original m2-atx has a mini-blade fuse standing in this place, because anything bigger than that won't fit that space

after you answering me this i will begin the testings :p
 
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Thread Starter

ViperRunner

Joined Jan 30, 2010
50
Put a bridge where the fuse was.
connect the inline fuse to +B.
In other words give the Power through a 2A fuse to +B and ACC, after bridging the fuse with solder.
You'll do just fine. I want you to test it.

see this link , then you'll get an idea
Hi again!

Sorry for my ignorance ;) already tested, and both the lines are with the right voltages! the 5v and the 12v!! :D

now do we have to try to arrange for substitutes to the two missing components, or should us only arrange for a diodo to put everything as it should and put the right fuse on it?
 

Thread Starter

ViperRunner

Joined Jan 30, 2010
50
Is the supply working without the load, if so explain your connection.
Better yet get a picture
I used a old car battery i have here to emulate the ideal condition on which this psu is used.. on a car :)

I keep this battery always well charged so it emulates well the condition!

After connecting, the PSU wasn't giving any voltages so i thinked, that as a regular psu it has to detect a motherboarb to turn on and give any sign of life!

So i picked up on some spared i had from a old psu and used the connector with it's cables and joined all the orange cables for the psu to sense a motherboard.. still no signal.. here i went remembering also it had to sense the on and off switch of the motherboard, so i also joined the green wire with a black one, and voilá! Power outputs on the red lines of 5v e in the yellow lines of 12v :D

[url=http://img268.imageshack.us/img268/9932/p1060247m.jpg]
[/URL]
 

R!f@@

Joined Apr 2, 2009
9,918
Good!! you are learning fast.
It's time to rap it up. Get 100nF 50V ceramic cap. and solder it to the diode location.
bridge the fuse with plenty of solder and put a 15A fuse via +B.
Then you are good to go.
BUT BE WISE NOT TO REVERSE THE SUPPLY CONNECTION, now since the diode is not there.
Cheers
 
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Thread Starter

ViperRunner

Joined Jan 30, 2010
50
Good!! you are learning fast.
It's time to rap it up. Get 100nF 50V ceramic cap. and solder it to the diode location.
bridge the fuse with plenty of solder and put a 15A fuse via +B.
Then you are good to go.
BUT BE WISE NOT TO REVERSE THE SUPPLY CONNECTION, now since the diode is not there.
Cheers
But it's not better to arrange for a diode to put there for security?

And why's the cap on the diode place?

sorry if this looks stupid questions for you, but i am intrigued :D
 

R!f@@

Joined Apr 2, 2009
9,918
I doubt that you can get a surface mount diode like the one before.
That is why I said to be careful on reverse connection. The diode is used to blow the fuse if the battery connection is reversed. Now that you know about it I think you will be careful not to be stupid on that matter.
The inline fuse is a better replacement than the soldered one. You can change it without a fuss.
Since getting a surface mount 100nF cap is difficult, I suggested you to get a normal ceramic with a label 104 and put it where the diode was.
Since that capacitor will be bigger than a chip it will be easier for you to solder it on the diode pads. The diode pads are same as the capacitor connections. Which is across +B and -B.

On the other hand, if you can find new surface mount chips then go ahead.
It's all up to you.
Now you know the supply is OK and only the bypass cap fused.
Probably it was an ignition spike.
Another method is to wire a 16V 1W zener across the battery connection.
This will be same as before. It will protect if a spike comes and will short circuit if the supply is reversed.
 

Thread Starter

ViperRunner

Joined Jan 30, 2010
50
I doubt that you can get a surface mount diode like the one before.
That is why I said to be careful on reverse connection. The diode is used to blow the fuse if the battery connection is reversed. Now that you know about it I think you will be careful not to be stupid on that matter.
The inline fuse is a better replacement than the soldered one. You can change it without a fuss.
Since getting a surface mount 100nF cap is difficult, I suggested you to get a normal ceramic with a label 104 and put it where the diode was.
Since that capacitor will be bigger than a chip it will be easier for you to solder it on the diode pads. The diode pads are same as the capacitor connections. Which is across +B and -B.

On the other hand, if you can find new surface mount chips then go ahead.
It's all up to you.
Now you know the supply is OK and only the bypass cap fused.
Probably it was an ignition spike.
Another method is to wire a 16V 1W zener across the battery connection.
This will be same as before. It will protect if a spike comes and will short circuit if the supply is reversed.
I know what you are meaning ;)

But before i was thinking in taking some surfice chip from a old motherboard or something like that, but how do i know the ones on the motherboard which are the righ values? and don't a motherboard have also the needed diode? if it don't, before you said it was possible to add regular diodes, and if i arrange one or a bunch of them together untill about 20amp?

sorry for being stuborn on this, but i like to think in the future tense, and i know that if it gives some trouble in some months or even years, i might not remember all we did on this, or some other person may make a mistake and reverse the input.. and then it all goes.. heheh :D
 
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