Capacitor Questions - which ones should I order?

[Etienne MacGyver]

will try to do a search for you , i guess 6.8 you write are μf ?

[Superully]

will try to do a search for you , i guess 6.8 you write are μf ?

yepp, 6.8μf. btw, what does that μf stand for?

[liquidx]

will try to do a search for you , i guess 6.8 you write are μf ?

yepp, 6.8μf. btw, what does that μf stand for?

A microfarad, so a thousandth of a farad which is a measure of capacitance.
Farads are big-ass things, so measures are mostly in fractions of them, microfarads, nanofarads, picofarads

They're named after Michael Faraday but in honour of the guy, he didn't discover/name them.
He was pretty busy though: http://en.wikipedia.org/wiki/Michael_Faraday

And that concludes today's history lesson

[McVenco]

µf means microfarad


To understand a bit more about caps, you could read about it here:

http://en.wikipedia.org/wiki/Capacitor
http://de.wikipedia.org/wiki/Kondensator_%28Elektrotechnik%29

Most of that is too technical for me as well (especially all those formulas), but it gives you a bit more information about what exactly a capacitor is and does. I started reading in those articles a while ago when I built a few guitar effects pedals from DIY kits, and I wanted to know what all those little thingies actually did with the signal.

Here's more:
http://en.wikipedia.org/wiki/Farad
http://en.wikipedia.org/wiki/Capacitance

Good luck with the whole cap-changing job!


edit: and what liquidx said 

[Superully]

And that concludes today's history lesson

thx ! that's the thing with the car, the cage and lightning, right?

[Superully]

OK ding-dong, here comes mr. knows-it-better.
Cap value actually doesn't always need to be exactly the same BUT, and it's a big BUT (Miss Piggy's ?): you need to know what you are doing !
So.......for instance.....if a cap is used as a filter cap in a power supply, there is no problem if you use a HIGHER value capacity.

just to make sure i'm not ordering wrong parts: you can always always always use higher voltages. it doesn't matter whether i use 25V or 250V instead of 16V - or should the replacement voltage value be close to the original one if i can't find the exact value?

AND you can't do anything wrong when you're using higher voltages even if the original ones are available?

BUT the capacity has to match on most occasions with a few exceptions ...

RIGHT or WRONG ?

[Etienne MacGyver]

Correct sir !  

you can always go up, never down on the voltage

if you need for example a 16V cap and you mount a 1000V , no problem for the value
it will be bigger so it could be that it will not fit on the board  

I mean try to mount this cap

in this position :


 

by the way , i looked for you on RS for the NP cap, and they are located under "audio & bipolar", but i did not see your value of 6,8...

I needed a few of these for gyruss's sanyo (audioboard section) and they where 4,7 wich do exist at RS
Now i dont know if this is a exeption that you can use another value since its a filtercap..

Maybe its for the audio part of that TV, but its hard to say that like this and without the schematics
if you cannot find it, i would leave the oldone in, and check after the rest if its nessesary to replace
(did that also with one cap of gyruss's monitor because it was bigger than the original and did not fit on the pcb...) 
anyway, no problems at gyruss monitor 

also i saw that one day you uploaded some videos from arcade repair tips to my ftp...

The "troubleshooting monitors with michael" videos also explain the voltage story on the capicitors
http://www.youtube.com/watch?v=QuTlChCko4k&feature=&p=B2F63700B630AEC0&index=0&playnext=1

[Superully]

holy moly - that's what i call BIG BLUE

[Superully]

by the way , i looked for you on RS for the NP cap, and they are located under "audio & bipolar", but i did not see your value of 6,8...

I needed a few of these for gyruss's sanyo (audioboard section) and they where 4,7 wich do exist at RS
Now i dont know if this is a exeption that you can use another value since its a filtercap..

Maybe its for the audio part of that TV, but its hard to say that like this and without the schematics
if you cannot find it, i would leave the oldone in, and check after the rest if its nessesary to replace

thx for checking, etienne. why did you check under "audio & bipolar"? wouldn't "bipolar" simply suffice? but whatever, a cap of that value doesn't exist in either section, so i guess i'll have to go with leaving it out completely. i COULD scan the schematics for you, but if we can't find the cap, what's the use of doing so?

i wish i had your desoldering station at hand, this would make the cap kit job so much easier!

[Etienne MacGyver]

thats exactly the reason, they dont exist in theyre site 

you can order this , its pretty cheap :



Or use wick,
and after all, caps are easy to remove, heat one pin while holding the cap under pressure to the other direction and repeat that process with the other leg , and vice versa  (wiggle it out)  understand me ?

[Superully]

already have a solder pump and the last cap kit i did was easier than i had expected, but it's time consuming and would probably be smoother with a desoldering iron. where's santa when you need him?

[liquidx]

And that concludes today's history lesson

thx ! that's the thing with the car, the cage and lightning, right?

Back to the future?

[Superully]

some more capacitor questions (for our wiki ):

- what do the individual markings on the capacitors mean? haven't been able to find info on it on the net ...



- is it ok to replace an 85°C cap with a 105°C version?

- one cap says (M) 85°C (6M) - what do those letters / numbers in brackets mean? especially (M) is something i've seen quite often!

[Etienne MacGyver]

those are not markings, they are "security vents"...  

Bulging of the vent on the top of the capacitor. (The 'vent' is the impression stamped in the top of the can. The impression forms the seams of the vent. It is designed so that if the capacitor becomes pressurized it will split at the vent's seams relieving the pressure rather than making it explode.)

Source.. (symptoms section)

And yes, ofcourse you can replace it with a higher temperature one, sometimes even better.
it means it can support this temperature, so ovious a 85 dergee cap will fail sooner or later at a temperature of lets say 100 degrees.

here a video of some guy blowing up caps, nice to see..

http://www.youtube.com/watch?v=9jDsNe_bmtE&feature=fvsr

[Superully]

thx etienne for clearing this up, i thought it might be some kind of cap indication. so basically it doesn't matter which vent is stamped on the capacitor.

as for the letters, any idea what (M) could mean? i now know that (NP) is for non-polarized and i'm happy that i've asked that question