Capacitor replacement question...
 

When replacing caps is there any thing special to look for. I know it
has to have the same capacitance, voltage, and temp is there something
else?


Also what are your opinions on using a higher voltage cap than was
originally used? For instance using a 35V when the original was a 25V.
The closer the better?

TIA!!

Slightly higher working voltage the better, just keep an eye out for the
correct polarity, don't wory too much about the temp.


Regards


"30W" wrote in message
...
When replacing caps is there any thing special to look for. I know it
has to have the same capacitance, voltage, and temp is there something
else?


Also what are your opinions on using a higher voltage cap than was
originally used? For instance using a 35V when the original was a 25V.
The closer the better?

TIA!!

"30W" wrote in message
...
When replacing caps is there any thing special to look for. I know it
has to have the same capacitance, voltage, and temp is there something
else?


Also what are your opinions on using a higher voltage cap than was
originally used? For instance using a 35V when the original was a 25V.
The closer the better?

TIA!!

Provided you have the space, higher temp and voltage rating the better. I
always use 105 degree caps and mostly 50v (in 5-25 volt applications).

"30W" bravely wrote to "All" (28 Dec 04 08:59:16)
--- on the heady topic of "Capacitor replacement question..."

30 From: 30W
30 Xref: aeinews sci.electronics.repair:4973

30 When replacing caps is there any thing special to look for. I know it
30 has to have the same capacitance, voltage, and temp is there something
30 else?

The capacitor type must be suitable for the application. For example
in a radio's output antenna circuit one would try to use a low loss
cap and for audio one would try to avoid ceramic types. Etc...


30 Also what are your opinions on using a higher voltage cap than was
30 originally used? For instance using a 35V when the original was a 25V.
30 The closer the better?

The importance of using the same voltage rating varies with capacitor
type. In general, the higher the voltage rating the larger the cap and
thus fitting the package size may be a problem. Also a larger voltage
rating basically implies a thicker dielectric and more heating of it.
So sometimes using an unnecessarily high voltage rating can actually
be deterimental in some circuits. Try to use the intended cap in the
design and only use a different type if you are sure of consequences.
Keep in mind that capacitance is capacitance no matter what cap type
but practical caps are not ideal devices and some will behave very
oddly when used in other than their intended way.

A*s*i*m*o*v

.... Dunno if we'll get that past the CSA und UL 'owever.

Cubzilla wrote:
Slightly higher working voltage the better, just keep an eye out for the
correct polarity, don't wory too much about the temp.

Whether or not the temp rating is important depends on the application.

E.g., it can be quite important in switching power supplies, which are
stressful for capacitors.


Regards


"30W" wrote in message
...

When replacing caps is there any thing special to look for. I know it
has to have the same capacitance, voltage, and temp is there something
else?


Also what are your opinions on using a higher voltage cap than was
originally used? For instance using a 35V when the original was a 25V.
The closer the better?

TIA!!






--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form .

Thanks alot for the help!!! Much appreciated!!

"30W" skrev i en meddelelse
...
When replacing caps is there any thing special to look for. I know it
has to have the same capacitance, voltage, and temp is there something
else?

The Application - If the capacitor needs to handle ripple currents as in a
switching power supply, or a snubber circuit, it needs to be rated for it.
Safety Capcitors need to be UL rated, etc.

Also what are your opinions on using a higher voltage cap than was
originally used?

Should be fine - if they are the same "technology"; i.e. it would be bad to
replace a polypropylene cap with a ceramic because the polyprop is there for
it's stable properties, while the ceramic is cheap.

What about electrolytic caps that do not have polarities? What are
they called and can the be replaced with electrolytic with polarities.

Thanks


On Tue, 28 Dec 2004 10:38:47 -0000, "Cubzilla"
wrote:

Slightly higher working voltage the better, just keep an eye out for the
correct polarity, don't wory too much about the temp.


Regards


"30W" wrote in message
.. .
When replacing caps is there any thing special to look for. I know it
has to have the same capacitance, voltage, and temp is there something
else?


Also what are your opinions on using a higher voltage cap than was
originally used? For instance using a 35V when the original was a 25V.
The closer the better?

TIA!!

Thanks what kind of caps are best for tv's/monitors

thanks again

On Tuesday, 28 Dec 2004 09:02:12 -500, "Asimov"
wrote:

"30W" bravely wrote to "All" (28 Dec 04 08:59:16)
--- on the heady topic of "Capacitor replacement question..."

30 From: 30W
30 Xref: aeinews sci.electronics.repair:4973

30 When replacing caps is there any thing special to look for. I know it
30 has to have the same capacitance, voltage, and temp is there something
30 else?

The capacitor type must be suitable for the application. For example
in a radio's output antenna circuit one would try to use a low loss
cap and for audio one would try to avoid ceramic types. Etc...


30 Also what are your opinions on using a higher voltage cap than was
30 originally used? For instance using a 35V when the original was a 25V.
30 The closer the better?

The importance of using the same voltage rating varies with capacitor
type. In general, the higher the voltage rating the larger the cap and
thus fitting the package size may be a problem. Also a larger voltage
rating basically implies a thicker dielectric and more heating of it.
So sometimes using an unnecessarily high voltage rating can actually
be deterimental in some circuits. Try to use the intended cap in the
design and only use a different type if you are sure of consequences.
Keep in mind that capacitance is capacitance no matter what cap type
but practical caps are not ideal devices and some will behave very
oddly when used in other than their intended way.

A*s*i*m*o*v

... Dunno if we'll get that past the CSA und UL 'owever.

"30W" wrote in message
...
| What about electrolytic caps that do not have polarities? What are
| they called

Non-polarized.

| and can they be replaced with electrolytic with polarities.

Sometimes by two back-to-back, each of which has double the capacity, but
otherwise no. What are they used for?

N

On Tue, 28 Dec 2004 08:59:16 GMT, 30W
wrote:

When replacing caps is there any thing special to look for. I know it
has to have the same capacitance, voltage, and temp is there something
else?


Also what are your opinions on using a higher voltage cap than was
originally used? For instance using a 35V when the original was a 25V.
The closer the better?

TIA!!

You can usually get away with the higher voltage rating if the app
isn't to critical.
What I do is get one with a much higher thermal rating.
Usually epoxy based.

Its for a TV. I am unsure what function the cap is serving as I was
unable to get a schematic for it from sams.

Thanks for your help


On Tue, 28 Dec 2004 20:56:24 GMT, "NSM" wrote:


"30W" wrote in message
.. .
| What about electrolytic caps that do not have polarities? What are
| they called

Non-polarized.

| and can they be replaced with electrolytic with polarities.

Sometimes by two back-to-back, each of which has double the capacity, but
otherwise no. What are they used for?

N

"30W" wrote in message
...
| Its for a TV. I am unsure what function the cap is serving as I was
| unable to get a schematic for it from sams.

I don't think I've ever heard of any TV that used a non-polarized
electrolytic. I don't see the point - they're used for AC motors and
sometimes for speaker networks only AFAIK.

Generally use the same or slightly higher voltage, the same or close
capacitance, temp is very dependent on usage, and watch out for ripple
current if they are main filter caps.

N

30W wrote:
Its for a TV. I am unsure what function the cap is serving as I was
unable to get a schematic for it from sams.


Are you sure you just haven't noticed the polarity marking(s)?

Thanks for your help


On Tue, 28 Dec 2004 20:56:24 GMT, "NSM" wrote:


"30W" wrote in message
. ..
| What about electrolytic caps that do not have polarities? What are
| they called

Non-polarized.

| and can they be replaced with electrolytic with polarities.

Sometimes by two back-to-back, each of which has double the capacity, but
otherwise no. What are they used for?

N





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The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form .

On Wed, 29 Dec 2004 06:59:37 GMT, CJT wrote:

30W wrote:
Its for a TV. I am unsure what function the cap is serving as I was
unable to get a schematic for it from sams.


Are you sure you just haven't noticed the polarity marking(s)?




Yeah im sure there is no polarity marking on it. Also there are no
polarity marking on the top and bottom of the PCB that all the other
electrolytics have. Im not sure of its function just know it was close
to fly back. Also its the only cap that is 85C on the whole board.

Thanks

"30W" wrote in message
...

| Yeah im sure there is no polarity marking on it. Also there are no
| polarity marking on the top and bottom of the PCB that all the other
| electrolytics have. Im not sure of its function just know it was close
| to fly back. Also its the only cap that is 85C on the whole board.

Why don't you post all the markings and a general description?

N

On Wed, 29 Dec 2004 06:35:51 GMT, "NSM" wrote:


"30W" wrote in message
.. .
| Its for a TV. I am unsure what function the cap is serving as I was
| unable to get a schematic for it from sams.

I don't think I've ever heard of any TV that used a non-polarized
electrolytic. I don't see the point - they're used for AC motors and
sometimes for speaker networks only AFAIK.

Generally use the same or slightly higher voltage, the same or close
capacitance, temp is very dependent on usage, and watch out for ripple
current if they are main filter caps.

N




Yeah its non-polarized all right. No marking on the cap or PCB. If I
get a chance I will take a few pictures of the cap. The cap looks a
little rough like it might be the culprit. The plastic casing going
around it looks like its burned a little. It was close to the flyback
and is the only cap on the board that is 85C.

Thanks

On Wed, 29 Dec 2004 06:35:51 GMT, "NSM" wrote:


"30W" wrote in message
.. .
| Its for a TV. I am unsure what function the cap is serving as I was
| unable to get a schematic for it from sams.

I don't think I've ever heard of any TV that used a non-polarized
electrolytic. I don't see the point - they're used for AC motors and
sometimes for speaker networks only AFAIK.

Generally use the same or slightly higher voltage, the same or close
capacitance, temp is very dependent on usage, and watch out for ripple
current if they are main filter caps.

N



Yeah im sure its a non polarized cap. There are no marking on the cap
or on the top or bottom of the pcb. All the other caps are marked with
polarities on the cap and a + - on top and bottom of the PCB.

It was clsoe to the flyback and it looks a little damaged. It looks
like the plastic film going around the cap is burnt. If i get a chance
I will take a few pictures.

Thanks

On Wed, 29 Dec 2004 19:21:15 GMT, "NSM" wrote:


"30W" wrote in message
.. .

| Yeah im sure there is no polarity marking on it. Also there are no
| polarity marking on the top and bottom of the PCB that all the other
| electrolytics have. Im not sure of its function just know it was close
| to fly back. Also its the only cap that is 85C on the whole board.

Why don't you post all the markings and a general description?

N



Ok heres all the markings....

Marcon
24085041
CE04W-BP
2.2uF
50V
85°C

"30W" bravely wrote to "All" (31 Dec 04 07:46:22)
--- on the heady topic of " Capacitor replacement question..."

30 From: 30W
30 Xref: aeinews sci.electronics.repair:5350

30 On Wed, 29 Dec 2004 19:21:15 GMT, "NSM" wrote:


"30W" wrote in message
.. .

| Yeah im sure there is no polarity marking on it. Also there are no
| polarity marking on the top and bottom of the PCB that all the other
| electrolytics have. Im not sure of its function just know it was close
| to fly back. Also its the only cap that is 85C on the whole board.

Why don't you post all the markings and a general description?

N


30 Ok heres all the markings....

30 Marcon
30 24085041
30 CE04W-BP
30 2.2uF
30 50V
30 850C


When the letters BP show up on an electro it often means Bi-Polar,
especially when there are no polarity markings. Sometimes the colour
of the label is different too, perhaps, green or orange, whatever...?

A*s*i*m*o*v

.... A fail-safe circuit will destroy others.

You don't see non-polarized in TV's real often, but you do see them; Mitsubishi
used lots of them in their late 80's early 90's chassis. Other mfr's use them
occasionally, never seen any real pattern for where they show up.