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

[baton]

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

Hello. Looking for D355

[Toasty]

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

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

[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.

.

[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?

[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?

[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

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

Picture. There are different parts surrounding the relay.

See post #12 for a picture.

[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

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

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

[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

thanks yur a life saver

[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.

[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

Do you get any "relay clicking" on the primary? All the other stuff (F1, R302 etc. mentioned in post 94) checks out?

[alez]

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

No, there is no sound. Stuff in the main supply section seems ok. Simply stand by supply does not work, the TOP is freezed by some side circuitry.
I'm using a 220 to 110 V transformer + a 150W bulb shunt. I correctly read 160VDC on the primary power rail capacitors. It's probably some transistor near Q856, but it's not easy to test&replace all as they are smd...

[Toasty]

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

The measurements that follow are done on the electrically HOT side with respect to earth ground. Contact by any part of your body with any exposed metal traces or components including but not limited to heatsinks, may result in injury or death. Follow the "one hand in your back pocket" rule when probing for these voltages.

Measurements are taken with the negative of your meter connected to the negative post of the bridge rectifier or like termination.

Set Meter to 20v DC range.

Confirm the following voltages at TOPSwitch TOP249YN with the power supply in Standby mode -

Pin 1: 5.8v
Pin 2: 2.4v
Pin 3: 1.3v
Pin 4: 0v
Pin 5: 5.8v

Set Meter to 200v DC range or higher.

Pin 7: 167v


Toast

[alez]

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

Thank you Toast for providing me those voltages... are those values taken from a working supply?
The readings at the TOP are quite identical:
Pin 1: 4.9v
Pin 2: 2.5v
Pin 3: 1.1v
Pin 4=0v
Pin 5: 4.9v
Pin 7: 160v
HDC rail: 160v
If I connect a 10k resistor between pin 1 and base of Q856, then pin 5 goes to 0v, but the circuit still doesn't work.

Alez

[Toasty]

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

Taken from a working 5v & 25v standby supply. The rest is still not working.

If those are present, then the TOP is working correctly. The ~160v output feeds directly to the standby transformer.


I've not gone back to figure the rest of the circuit.