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

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

Super Moderator
Most Helpful Member
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.
 
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

Super Moderator
Most Helpful Member
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 :D

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 http://www.lpilsley.co.uk/msspict.htm

C8 in this one http://www.lpilsley.co.uk/sspict.htm

C209 in this one http://www.lpilsley.co.uk/grd3pic.htm

C610 in this one http://www.lpilsley.co.uk/srd510_1.htm
 

Ylli

Active Member
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

Super Moderator
Most Helpful Member
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.
 
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.
 
I don't think so :D

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 http://www.lpilsley.co.uk/msspict.htm

C8 in this one http://www.lpilsley.co.uk/sspict.htm

C209 in this one http://www.lpilsley.co.uk/grd3pic.htm

C610 in this one http://www.lpilsley.co.uk/srd510_1.htm
Yeah, that was a typo I meant pF not
I don't think so :D

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 http://www.lpilsley.co.uk/msspict.htm

C8 in this one http://www.lpilsley.co.uk/sspict.htm

C209 in this one http://www.lpilsley.co.uk/grd3pic.htm

C610 in this one http://www.lpilsley.co.uk/srd510_1.htm
Yeah that was a typo
 

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