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Electrolytic Capacitors and life span

What is the life span of an electrolytic capacitor?
In a 26 year-old piece of video equipment, should I replace all the
electrolytic caps with such ratings as 4.7uf @25v or just concentrate
on the high voltage ones like 10uf @ 450v.
Which ones are more prone to failure under normal use?
 
S

Sam Goldwasser

Jan 1, 1970
0
What is the life span of an electrolytic capacitor?
In a 26 year-old piece of video equipment, should I replace all the
electrolytic caps with such ratings as 4.7uf @25v or just concentrate
on the high voltage ones like 10uf @ 450v.
Which ones are more prone to failure under normal use?

Why do you want to replace any? It all depends on not only age, but use,
temperature, type of capacitor, stress (rippled current, etc.), and more.
In some instances, they will last 50 years. in others, they won't go
past 10.

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J

Jerry G.

Jan 1, 1970
0
The caps that will wear out, are the ones that are under heat and operation
stress. The caps under little stress will most likely be okay. If you
blindly replace caps, you will most likely be changing ones that are still
working okay. Use proper troubleshooting techniques to determine the worn
down ones, and replace them as necessary. It is not only caps that go bad in
older equipment. The various other parts can also drift off value with age.

--

Jerry G.
======


What is the life span of an electrolytic capacitor?
In a 26 year-old piece of video equipment, should I replace all the
electrolytic caps with such ratings as 4.7uf @25v or just concentrate
on the high voltage ones like 10uf @ 450v.
Which ones are more prone to failure under normal use?
 
N

N Cook

Jan 1, 1970
0
What is the life span of an electrolytic capacitor?
In a 26 year-old piece of video equipment, should I replace all the
electrolytic caps with such ratings as 4.7uf @25v or just concentrate
on the high voltage ones like 10uf @ 450v.
Which ones are more prone to failure under normal use?

I looked on my repair1.htm file which has 88 vcr repair briefs,
only 5 faults concerned electrolytics. If 85 degree C caps
in screened ps then perhaps replace with 105 deg C. Otherwise
my mantra is
"If it aint broke , don't poke"

electronic hints and repair briefs , schematics/manuals list on
http://homepages.tcp.co.uk/~diverse
 
M

me

Jan 1, 1970
0
I looked on my repair1.htm file which has 88 vcr repair briefs,
only 5 faults concerned electrolytics. If 85 degree C caps
in screened ps then perhaps replace with 105 deg C. Otherwise
my mantra is
"If it aint broke , don't poke"

Often you'll find bad capacitors will leave a trace, most commonly burning
up resistors in PS filter circuits. Some capacitors are common failure
parts (some Bendix weather radar systems for example) and are routinely
replaced on any service call. After 26 years, if you are replacing
anything on it, you might as well replace the electrolytics also...
 
M

Matt J. McCullar

Jan 1, 1970
0
What is the life span of an electrolytic capacitor?
In a 26 year-old piece of video equipment, should I replace all the
electrolytic caps with such ratings as 4.7uf @25v or just concentrate
on the high voltage ones like 10uf @ 450v.
Which ones are more prone to failure under normal use?

Try doing a search to see if there is a regular failure in that particular
piece of equipment. Other posters are correct when they say that there are
many applications in which an electrolytic will work just fine for ages,
whereas in others they go bad pretty quickly.

Heat is the enemy. This is particularly true inside video monitors and in
power supplies. Electrolytics really get a workout in these things, anyway.
With a bit of practice you will be able to tell just by looking at a cap
that if it's not bad, it certainly warrants being tested. Discoloration,
shrunk plastic wrapper, or even by funny smell.
 
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