Help Required - Repairing a Logitech Z906 Speaker

[Amarbir[Lynx-India]]

Hello Guys ,
     Got One Z906 From My Client .Opened The Woofer That Has all the electronics and boy i am impressed .My testing shows that due to a lousy UPS he has blown up the stage in the primary till the Rectifiers .The rectifiers seem all ok .Not tested anything beyond that .The is what i think is wrong need some advise here

1 : AC input goes through 2 fuses in both neutral and phase supply Both Blew Up.Then There was a component With a Marking "RV1 " .I suspect it should be a RDN rated at 275 volts or something .It can /cannot be a thermistor [ ptc ] ,But God Knows ,This Too Blew Up And I See a half inch pcb just becoming toast .Then the Neutral and phase supply had a capacitor i have no idea what it was its just melted due to rv1 component blasting .After this it was the choke that seems fine ,then the path routes to another capacitor like the capacitor i had just mentioned [ Will this capacitor after the choke and before the choke be same ? ,I do not think so ] ,The One after the choke is 1.0k275v-x2 . Then again we have a choke that seems ok too and then the supply goes to the 4 rectifiers ,they seem good too .so i suspect rest will be good too .please help me find what there in the rv1 and the first capacitor .Any idea i can make it work by just connecting the choke to the supply the first one but then this is not good repairing 

[T4P]

It's not gonna help you or us if you don't post any pictures

And if you aren't too sure, those are definitely Class X2 and Class Y2 caps for EMI filtering and the like http://www.justradios.com/safetytips.html

[Amarbir[Lynx-India]]

It's not gonna help you or us if you don't post any pictures

And if you aren't too sure, those are definitely Class X2 and Class Y2 caps for EMI filtering and the like http://www.justradios.com/safetytips.html

Sir ,
    I Will Read This Website And Post The Pictures in The Morning Its 2:00 Am Here Lol  [ India ]

[Amarbir[Lynx-India]]

It's not gonna help you or us if you don't post any pictures

And if you aren't too sure, those are definitely Class X2 and Class Y2 caps for EMI filtering and the like http://www.justradios.com/safetytips.html

Sir ,
     Please Find The Pictures Of This Busted Unit .Both The Fuses values i have a idea as they are printed on pcb .No Idea of the RV1 and The first cap that looks similiar like the other cap "Yellow Colour " .The Unit can surely work "IMHO" With the Two components but They are there for a reason and i would not like to change that 

[Rerouter]

the 2 yellow things are big mains rated multi-layer ceramic caps, class x2,

as for what blew up, i could only imagine something like a Metal-oxide-varistor making that big a scorch mark, when you exceed the rated voltage they short themselves to blow the fuses, and in the process can dump out a few hundred watt for a short moment

[Amarbir[Lynx-India]]

the 2 yellow things are big mains rated multi-layer ceramic caps, class x2,

as for what blew up, i could only imagine something like a Metal-oxide-varistor making that big a scorch mark, when you exceed the rated voltage they short themselves to blow the fuses, and in the process can dump out a few hundred watt for a short moment

Sir ,
     I Read With Great interest the link Mr Dave had send me in this post "I suggest everyone should read that " . I have checked it again .The RDN/MOV is one of the components .I plan to use the 275 Volts rated one this time .The Capacitor Surely is a AC Live To Neutral Type It Has to be X2 .My Question is Can Someone Tell Me What Was The exact X2 capacitor value in pic 3

[Kilroy]

My Question is Can Someone Tell Me What Was The exact X2 capacitor value in pic 3

Sure...1uF.

[SeanB]

1uF 275VAC class X2. You can use almost any value between 0.47uF to 1.5uF 275 VAC that will fir the pin spacing. the actual value here is not very important, as long as it is higfh enough to provide some filtering.

Good thing the MOV was fitted, it definitely gave itself heroically to save the rest of the circuit.

[Amarbir[Lynx-India]]

Hi Guys [ Everyone ] ,
 Thanks For Making My Task Easier ,I Appreciate That ,Would Get Back To You folks With The Repair Job With Pictures .

[Amarbir[Lynx-India]]

Hello Friends ,
       This is What i did .Took 2 fuses 250 volts 6 Amps and 2.5 amps .Fixed Them In the start of This circuit .Then Connected a 14D431K Varistor [ MOV ] In Parallel .Took Out a Old X2 Same Microfarad But 250 Volt Cap From a Old Monitor PCB Plate .This was much bigger then the one that was busted .So i gluesticked it on top of the other X2 cap And connected the same with wires to the MOV in parallel .The output then crossed a choke and was again filtered by the second X2 .As soon as i was starting the unit the Fuse section was going in flames again and again .Nothing was getting busted but  [ I did remove the second choke after the second x2 cap ,so that the primary smps voltage was even reaching the rectifiers ] . I could not solve the arching in the busted section of the pcb .Finally i cut all the tracks there and made a 1 inch hole and rearranged the fuses and voila "The circuit was alive ".Fitted  the second choke back and the circuit was alive .Thanks to all of you who guided me in this and the once who though to write something but never did and the once who just read and went off ;-)

PS :  Let The Pictures Talk

[Rerouter]

a few thoughts come to mind, HEAT-SHRINK!, TAPE!, SOMETHING!, those contacts will be live, at least cover them so that if your glue fails you don't re-blow your fuses, or much much worse,

[Amarbir[Lynx-India]]

a few thoughts come to mind, HEAT-SHRINK!, TAPE!, SOMETHING!, those contacts will be live, at least cover them so that if your glue fails you don't re-blow your fuses, or much much worse,

Sir ,
    Before i Did the final inspection i did all that you advised .

[Rerouter]

i wanted to be safe, as your images showed no sign of anything,

there isnt enough people who know which end of the soldering iron to hold to risk having them zap themselves

[pepitopepito]

Hi,
My Z906 subwoofer doesnt work and smells as burnt when AC connected. How do you open it to see the pcb? I got all screws but seems imposible to open from the back side....

[Amarbir[Lynx-India]]

Hi,
My Z906 subwoofer doesnt work and smells as burnt when AC connected. How do you open it to see the pcb? I got all screws but seems imposible to open from the back side....

Well,
    Treat It Like a Wife Not a Girlfriend  .Only a Screwdriver is Required To Open The Same  .Where Are You From

[pepitopepito]

Hi, I am writing from Spain.
After making some stripes while trying to separe the back metal piece from the box I hope my wife will no suffer so much...
Do I have to get the whole metal  piece or only the plastic piece (the one where connectors are located)?

Enviado desde mi LG-P990 usando Tapatalk

[Amarbir[Lynx-India]]

Hi, I am writing from Spain.
After making some stripes while trying to separe the back metal piece from the box I hope my wife will no suffer so much...
Do I have to get the whole metal  piece or only the plastic piece (the one where connectors are located)?

Enviado desde mi LG-P990 usando Tapatalk

Well,
 i do not remember but check out yu can clearly see you can remove all screws and whamm it comes our .Its connected to back using a glue type sealant  .you have to use some force .

[pepitopepito]

Perfect, the problem was the glue.
Now the new problem calls burnt pcb close to the transformer... is there any schema to know which were the burnt pieces? If not, do you know if logitech sells pieces

[Amarbir[Lynx-India]]

Perfect, the problem was the glue.
Now the new problem calls burnt pcb close to the transformer... is there any schema to know which were the burnt pieces? If not, do you know if logitech sells pieces

Hello ,
     I and all will appreciate a complete picture of the power supply block please .i just repaired one and do not remember everything now

[pepitopepito]

Like this is ok?

[pepitopepito]

2 Pictures from the other side

[Amarbir[Lynx-India]]

Sir ,
     How Good Are You in repairs this repair would depend on this question .If you like to understand how to repair smps i would recommend you get some book and try this one .Or give it to a repair tech doing smps repair since a few years .

[pepitopepito]

Hi, I do not have much experience in these questions, but I'll find someone that will do it for me. Do you have schematics and info about reference of burnt pieces?

Enviado desde mi LG-P990 usando Tapatalk

[pepitopepito]

Hi, did you find schematics?

Enviado desde mi LG-P990 usando Tapatalk

[TheHiFi]

Hi, I need some help with logitech z906's psu board components. I am looking for help with these components values: R37;R25;R24;R22;R21;C7;R13;C61.