How to test a Ceramic Capacitor?
 

hello,
I heard that Ceramic Capacitors rarely fail nevertheless how can one be
sure? Is there a way to test them to know if they are good? Is it
important to test these or not? Any help would be appreciated!

you can test for shorts or leakage with a standard VOM or DMM and then check
for proper capacitance value with a cap meter or DMM with capacitance
feature.

--
Best Regards,
Daniel Sofie
Electronics Supply & Repair
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wrote in message
oups.com...
hello,
I heard that Ceramic Capacitors rarely fail nevertheless how can one be
sure? Is there a way to test them to know if they are good? Is it
important to test these or not? Any help would be appreciated!

" bravely wrote to "All" (12 Sep 05 08:36:24)
--- on the heady topic of "How to test a Ceramic Capacitor?"

mi From:
mi Xref: core-easynews sci.electronics.repair:341943

mi hello,
mi I heard that Ceramic Capacitors rarely fail nevertheless how can one
mi be sure? Is there a way to test them to know if they are good? Is it
mi important to test these or not? Any help would be appreciated!

Ceramics can be checked for power factor and compared to the typical
rated specification of the equivalent new part. However, usually all
that is needed is a scope, since an abnormal signal is often a clue
that the cap is not working right. They don't often fail except in
high energy circuits but then they are also less used in these because
of their many disadvantages.

In general, ceramic capacitors, and other types, have losses that
increase with frequency. They behave as if they have a little bit of
series resistance and thus get hot. As you know heat is the enemy of
all components, because it often increases leakage curents and can
turn them into charcoal. Also when components heat and cool cyclically
there is a mechanical expansion and contraction that results in
material fatigue such that internal breaks can develop.

A*s*i*m*o*v

.... Your E-Mail has been returned due to insufficient voltage.

"Asimov" wrote in
:

" bravely wrote to "All" (12 Sep 05 08:36:24)
--- on the heady topic of "How to test a Ceramic Capacitor?"

mi From:
mi Xref: core-easynews sci.electronics.repair:341943

mi hello,
mi I heard that Ceramic Capacitors rarely fail nevertheless how can one
mi be sure? Is there a way to test them to know if they are good? Is it
mi important to test these or not? Any help would be appreciated!

Ceramics can be checked for power factor and compared to the typical
rated specification of the equivalent new part. However, usually all
that is needed is a scope, since an abnormal signal is often a clue
that the cap is not working right. They don't often fail except in
high energy circuits but then they are also less used in these because
of their many disadvantages.

In general, ceramic capacitors, and other types, have losses that
increase with frequency. They behave as if they have a little bit of
series resistance and thus get hot. As you know heat is the enemy of
all components, because it often increases leakage curents and can
turn them into charcoal. Also when components heat and cool cyclically
there is a mechanical expansion and contraction that results in
material fatigue such that internal breaks can develop.

A*s*i*m*o*v

... Your E-Mail has been returned due to insufficient voltage.



I used to run them up on a TEK curve tracer,either a 576 or the 7K 7CT1N I
had in my bench scope.(I loved that little plug-in,it was SO useful).
They form a loop and if there's breakdown,the loop closes,it shows
intermittents and temp sensitivity,too.You can compare to a new cap,too.
I used the CT on caps from 0.1uf dip caps to HV caps.

--
Jim Yanik
jyanik
at
kua.net