How do I find the value of an exploded ceramic capacitor?

[RayRay1132]

So I got an old Sharp LCD tv from a friend and he said it hadn't worked in over a year so he gave it to me. When I plugged it in it made an arcing noise and the power and OPC lights were flashing; then the arcing stopped and I smelled something burning so I opened the case an plugged it in again and found a ceramic capacitor in the power supply board arcing. The capacitor's case was completely blown open and there were no markings on the other side. I think its a ceramic disk capacitor. I also looked online but I couldn't find a schematic for my PSU board. Any Ideas on how to go about replacing it???
PSU Model - rdenca336wjqz
Tv Model - Sharp Aquos LC-C5277UN

Best Regards - Ray

 

[Nigel Goodwin]

You need to find what value it is - however, they may not be a schematic available - it's been common practice for a good few years now for repairs to be PCB replacements only, and no schematics (even for dealers).

Assuming it's a little blue disc capacitor? (they are usually, but not always, blue), such capacitor have been a VERY common failure for decades - if you check what it's circuit reference is (C123 or whatever) you may be able to find some mention by googling that with the model number (it's highly likely it's a very common failure). I used to keep a drawer full of all the different values I could source for those capacitors, as they were such a common fault going back long in the CRT days.

 

[RayRay1132]

You need to find what value it is - however, they may not be a schematic available - it's been common practice for a good few years now for repairs to be PCB replacements only, and no schematics (even for dealers).

Assuming it's a little blue disc capacitor? (they are usually, but not always, blue), such capacitor have been a VERY common failure for decades - if you check what it's circuit reference is (C123 or whatever) you may be able to find some mention by googling that with the model number (it's highly likely it's a very common failure). I used to keep a drawer full of all the different values I could source for those capacitors, as they were such a common fault going back long in the CRT days.

Thanks, I tried looking it up but I couldn't find any info so I took a 1kv 50uf cap and soldered it on and it seems to work just fine.

 

[Nigel Goodwin]

Thanks, I tried looking it up but I couldn't find any info so I took a 1kv 50uf cap and soldered it on and it seems to work just fine.

I don't think so

Bit of a typo there - don't think you meany micro! - or it was a VERY large capacitor.

Those failing capacitors are usually either across the chopper transistor, or in series with a diode across the primary of the chopper transformer - in neither case is the value critical. Here are some representative values in satellite receiver PSU's.

C57 in this circuit

C8 in this one

C209 in this one

C610 in this one

 

[Ylli]

Or it may have been a 'safety' cap across the line or between line and chassis. In which case the value is not as critical as long as it is no too large (<0.047 uF)

 

[Nigel Goodwin]

Or it may have been a 'safety' cap across the line or between line and chassis. In which case the value is not as critical as long as it is no too large (<0.047 uF)

Highly unlikely, those safety caps only fail VERY rarely (and usually due to lightning damage), whereas the small blue 1000V ones fail a GREAT deal. As I mentioned above, I used to have a specific drawer just for those capacitors.

 

[RayRay1132]

Highly unlikely, those safety caps only fail VERY rarely (and usually due to lightning damage), whereas the small blue 1000V ones fail a GREAT deal. As I mentioned above, I used to have a specific drawer just for those capacitors.

Yeah it was a small blue one that failed.

Highly unlikely, those safety caps only fail VERY rarely (and usually due to lightning damage), whereas the small blue 1000V ones fail a GREAT deal. As I mentioned above, I used to have a specific drawer just for those capacitors.

Highly unlikely, those safety caps only fail VERY rarely (and usually due to lightning damage), whereas the small blue 1000V ones fail a GREAT deal. As I mentioned above, I used to have a specific drawer just for those capacitors.

Yeah, it was a small blue one.

 

[RayRay1132]

I don't think so

Bit of a typo there - don't think you meany micro! - or it was a VERY large capacitor.

Those failing capacitors are usually either across the chopper transistor, or in series with a diode across the primary of the chopper transformer - in neither case is the value critical. Here are some representative values in satellite receiver PSU's.

C57 in this circuit

C8 in this one

C209 in this one

C610 in this one

Yeah, that was a typo I meant pF not

I don't think so

Bit of a typo there - don't think you meany micro! - or it was a VERY large capacitor.

Those failing capacitors are usually either across the chopper transistor, or in series with a diode across the primary of the chopper transformer - in neither case is the value critical. Here are some representative values in satellite receiver PSU's.

C57 in this circuit

C8 in this one

C209 in this one

C610 in this one

Yeah that was a typo