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Main => Monitor/Video Forum => Topic started by: dssrocks on November 13, 2016, 11:36:23 pm

Title: Caps new vs old
Post by: dssrocks on November 13, 2016, 11:36:23 pm
Hello I have a cap tester and I was wondering if the cap reads the correct mf with the tester does it mean it is good? Other than for longevity is there any advantage to replace an old cap with new?
Title: Re: Caps new vs old
Post by: ed12 on November 13, 2016, 11:58:35 pm
its a full debate
in my shop it is 5years or less (common valuve only)
in others it 10 years
other ppl say no i will hang on to them
in short its a matter of to each there own

ed
Title: Re: Caps new vs old
Post by: Titchgamer on November 14, 2016, 07:26:25 am
In my world you leave em be until they are duff.
As the old saying goes dont fix what aint broke.
Title: Re: Caps new vs old
Post by: lilshawn on November 14, 2016, 02:26:36 pm
old caps where made a little better than nowadays.

new cap lifetimes these days are measured in HOURS not years. A GOOD quality cap will be about 5000 hours...with decent quality caps at ~3000. cheap chinese? who knows...are they even IN spec to begin with?

still, if what you have is old and has original caps AND it works... leave it.

if what you have is old and has original caps AND it has issues commonly associated with dead or dying caps... change them.
Title: Re: Caps new vs old
Post by: ed12 on November 14, 2016, 02:42:30 pm
as a rule of thumb
we recap all caps
this gives more Reliability in the repair
it also takes 1 question out of a repair (nothing like getting a unit back) because u did a half ass job of it
the down side is yes i go through about 100 of each common cap value a week or 2
if u do the math u will soon find out why
motherboard 1000/6.3 x 6
motherboard 1-10mf 12v x6-10
that is pre board
and only 1 side of it
amps/monitors/lcd
and u will soon get the point

ed
Title: Re: Caps new vs old
Post by: Titchgamer on November 14, 2016, 05:32:59 pm
Long as the dont look like this one I pulled out of a compressor the other day :p
(http://uploads.tapatalk-cdn.com/20161114/01d856cedc210acd8d186234758ff92d.jpg)
Title: Re: Caps new vs old
Post by: lilshawn on November 14, 2016, 07:43:27 pm
Long as the dont look like this one I pulled out of a compressor the other day :p
(http://uploads.tapatalk-cdn.com/20161114/01d856cedc210acd8d186234758ff92d.jpg)

YYYYYYEEEEEECCCCHHH!

 :lol

THAT IS PRETTY FOOKED
Title: Re: Caps new vs old
Post by: Titchgamer on November 15, 2016, 02:38:53 am
Made for easy fault finding though :p
Title: Re: Caps new vs old
Post by: nburgmeijer on November 15, 2016, 08:27:50 am
It never hurts to replace the caps.
The real problem of todays electronics is the use of cheap capacitors from China(China also has some good producers of caps). These are rated @ 85 degrees celsius, and are poorly constructed.
The biggest influence on a caps lifespan is the temperature. Consider the ambient temperature in your cabinet.
Bad construction leads to high ESR(equivalent series resistance) which makes the caps heat up a lot more than caps with low ESR.
That said. Any current consumer electronics shouldn't be thrown away when faulty. Replace caps and see what happens!

Back to caps for monitors:
- You want at least 105 degrees celcius rated caps.
- The ESR should not exceed expected limits (or as low as reasonably possible).
- Caps last a lot longer if you de-rate them. So if a cap is 100 uF/16V, replace it by a 100uF/25V for example.
- Don't buy  cheap crappy chinese caps.

Here's a quote about some brands:

Quote
All Japanese caps are considered of high quality, and we like to see the following cap brands:

Rubycon
United Chemi-Con (or Nippon Chemi-Con)
Nichicon
Sanyo/Suncon
Panasonic
Hitachi
FPCAP or Functional Polymer Capacitor (ex-Fujitsu caps segment, which was bought by Nichicon)
ELNA

Besides Japanese manufacturers there are also several US and European vendors that make high-quality capacitors. Probably we won't meet any of the below cap brands inside a consumer grade PSU, at least their electrolytic offerings, but we decided that it still worth mentioning them.

Cornell Dubilier (USA)
Illinois Capacitor (Currently owned my Cornell Dubilier)
Kemet Corporation (USA)
Vishay (USA)
EPCOS (TDK company, Germany)
Würth Elektronik (Germany)

And lastly if you have a good cap tester that can test ESR. Then measure it and compare it to some lists for max ESR found on the net.
Caps can still have the correct capacitance but a high ESR!
Title: Re: Caps new vs old
Post by: lilshawn on November 15, 2016, 02:47:44 pm
be warned... "All Japanese caps are considered of high quality" are often counterfeited because they are good and fetch a premium price.

you can guarantee with absolute certainty that any of those brands found on ebay are fakes.
Title: Re: Caps new vs old
Post by: behrmr on November 15, 2016, 02:58:16 pm
Get your caps from IanKellog.com or arcadepartsandrepair.com and you won't have to worry about whether or not they are counterfeit or old or bad.  These guys stock the good parts and sell enough that you know you're getting newer caps vs. new caps that have been on the shelf for 10 years.  Avoid Bob Roberts cap kits and fly back transformers.   I don't buy any electronic parts from him anymore.
Title: Re: Caps new vs old
Post by: mclovin on November 17, 2016, 12:23:41 am
Here is my theory, if it is your game to keep then buy a cap kit and replace everything, its cheap insurance. If you are doing repairs for someone else or you plan on selling the game just replace the bad ones. This is not due to greed but just for the simple fact that i like to have stock of some caps or would just buy locally because I hate waiting for stuff to be shipped. Just my .02.