LiteOn PA-6601-1A (600w) blows its TOP

[alez]

Re: LiteOn PA-6601-1A (600w) blows its TOP

So after replacing U801, Q856 and OPTO851, I have a fully working PSU.

Hi all. I have the same problem. I have replaced the TOP, its cap, Q856 (with a bc557) and OPTO851 (with a sharp pc123). It is still dead...what to replace now?
Seems that Q856 lowers TOP's frequency in stand by mode. A way would be tring to bypass some circuitry as the TOP should work "alone". What do you think?

-Alez

[godonr]

Re: LiteOn PA-6601-1A (600w) blows its TOP

Toasty -- I was referring to C301, 302 and 303 not the mains. Duties have pulled me off this p/s but I still have "a ton" of them around and it bugs me I was never able to fix this problem.
Sigma -- please post if you are successful in repairing your supply. It's the burnt R302 problem, right? Known things that go are F1, R302, Q301 & Q302 and C301,302 & 303. Would love to know if you are successful.

[sigma]

Re: LiteOn PA-6601-1A (600w) blows its TOP

thanks yur a life saver

[Toasty]

Re: LiteOn PA-6601-1A (600w) blows its TOP

Inrush Current Limiter, NTC thermistor

SCK-055 - All at 25°C:
5Ω cold resistance
5A max. constant current
166mΩ working resistance

This will work and with a bit more current handling:
http://search.digikey.com/scripts/Dk...me=495-2103-ND

Use a 100w to 200w light bulb in series with mains when testing. Saves fuses and these.

See post 23 here:
https://www.badcaps.net/forum/showthread.php?t=7165

.

[sigma]

Re: LiteOn PA-6601-1A (600w) blows its TOP

Lol, yes I did ..... my initial troubleshooting approach was a bit primitive....

[Toasty]

Re: LiteOn PA-6601-1A (600w) blows its TOP

You burnt THAT!?!? OMG!

Did the fuse blow too?

You must have -really- pissed it off!

[sigma]

Re: LiteOn PA-6601-1A (600w) blows its TOP

Ok so looking at pic 2 from post #12 its the greenish circle glued to the side of REL1. (I'm on my phone right now so when I get home I'll take a pic of where it was )

[Toasty]

Re: LiteOn PA-6601-1A (600w) blows its TOP

Picture. There are different parts surrounding the relay.

See post #12 for a picture.

[sigma]

Re: LiteOn PA-6601-1A (600w) blows its TOP

i can't id the part cause it was glued to the board with white epoxy like adhesive to the main relay and i can't remove the epoxy from the board to see the part number. it's the part that is with REL1

[Toasty]

Re: LiteOn PA-6601-1A (600w) blows its TOP

>>Just wondering if anyone found the problem when these supplies take out F1, R302 transistor and caps on the primary side?<<

Primary caps?? Never have seen that...?

>><snip>...I can't identify it cause it broke apart. Can anyone tell me what type and value it was?<<

I can't help you until you reveal its ID number. R???

Toast

[sigma]

Re: LiteOn PA-6601-1A (600w) blows its TOP

Hi guys I'm new here, I was troubleshooting one of these power supplies and was able to narrow the problem down thanks to this post. Unfortunately b4 I found the problem I futher damaged the PS whole troubleshooting, another component burnt besides the R302, it's the resistoe next to the relay. I can't identify it cause it broke apart. Can anyone tell me what type and value it was?

[godonr]

Re: LiteOn PA-6601-1A (600w) blows its TOP

Just wondering if anyone found the problem when these supplies take out F1, R302 transistor and caps on the primary side?

[Toasty]

Re: LiteOn PA-6601-1A (600w) blows its TOP

Schottky diode in SOT-23 package.

Marked 5H.

From Post 58.

Which crosses to MMBD701.

.

[Toasty]

Re: LiteOn PA-6601-1A (600w) blows its TOP

What is it? Where? Picture or nearby area information please.

[baton]

Re: LiteOn PA-6601-1A (600w) blows its TOP

Hello. Looking for D355

[Fallen Wolf]

Re: LiteOn PA-6601-1A (600w) blows its TOP

Just wanted to leave feedback: I've given up on the broken supply here - mostly because I couldn't find some replacement-parts here in Germany (mostly the capacitors around R302 - shipping-costs from mouser and digikey to Germany are overkill...) and because I got a used-one in working-condition from Ebay

Hopefully the one from Ebay will last for a while.

I started to make a list of the parts on the board (attatched to this post - only some of the electrolytic-capacitors are listed and it's in German ^^ ), so if anyone may find this incomplete list useful, here you go

Thanks for all your help
Greetings from Germany
Wolfi

[godonr]

Re: LiteOn PA-6601-1A (600w) blows its TOP

Toasty -- I can appreciate that. The blown TOP is an easy fix but the other is (F1, etc) tough. I think the problem is in the mains and may be the power corrector. I'm tracking a working one, printing out data sheets and hope to find something soon. I finally have a "spare" working supply I can make a mistake with and not worry about. As always, thanks for the input!

[Toasty]

Re: LiteOn PA-6601-1A (600w) blows its TOP

As I only have 1 to play with, I shelved this for the time being. I bought it just to see what I could determine, but also reached a wall where it sounded like it was going to fire, but doesn't.

Other, easier fixes are making money, so this will sit for awhile.

Toast

[godonr]

Re: LiteOn PA-6601-1A (600w) blows its TOP

Attached are two more pixs of the primary side. On a good supply, I see 350v on the cathode side and 52v on the anode. On a bad board with F1, Q301, C301 and C302 and R302 all replaced (obvious damage to all), I still don't get any voltage at D1. Source seems to trace to L4981AD shown on solder side picture. Is there a safe way to read it????

PS... Toasty, that last post about the opto (#76)... it fixed a board where U801 had blown. So far they are the easiest to fix.

[godonr]

Re: LiteOn PA-6601-1A (600w) blows its TOP

Have a huntron which will sig them... but really had replaced everything else on one supply with no luck so I tried the 851 (It had worked on a blown U801 once) and got everything back. Basically shotgunning at this point cause board has me confused.