Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems.

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1   Report Post  
Posted to sci.electronics.repair
external usenet poster
 
Posts: 23
Default Variation in usable capacitor ratings?

Hi everyone,

I've been upgrading a simple power supply in a satellite receiver
using a kit provided by a company selling spares.

I've noticed that there's quite a bit of difference between the
original capacitor values and the upgraded replacements provided, for
instance

Old New

47uF, 35V 100uF, 35V
2200uF, 10V 2200uF, 16V
330uF, 16V 470uF, 35

etc

My querstion is: do the upgraded capacitors only work together as a
set or can any one of them be replaced with the upgraded value?

In the latter case, a follow-up quesion would be how much variation in
capacitor value is permissible (presumably as long as it's higher)?

  #2   Report Post  
Posted to sci.electronics.repair
external usenet poster
 
Posts: 2,770
Default Variation in usable capacitor ratings?



Art Deco wrote:

Hi everyone,

I've been upgrading a simple power supply in a satellite receiver
using a kit provided by a company selling spares.

I've noticed that there's quite a bit of difference between the
original capacitor values and the upgraded replacements provided, for
instance

Old New

47uF, 35V 100uF, 35V
2200uF, 10V 2200uF, 16V
330uF, 16V 470uF, 35

etc

My querstion is: do the upgraded capacitors only work together as a
set or can any one of them be replaced with the upgraded value?


In any combination you like.


In the latter case, a follow-up quesion would be how much variation in
capacitor value is permissible (presumably as long as it's higher)?


It's just a *maximum* voltage.

Graham


  #3   Report Post  
Posted to sci.electronics.repair
external usenet poster
 
Posts: 23
Default Variation in usable capacitor ratings?

On Thu, 19 Oct 2006 14:53:37 +0100, Eeyore
wrote:



Art Deco wrote:

Hi everyone,

I've been upgrading a simple power supply in a satellite receiver
using a kit provided by a company selling spares.

I've noticed that there's quite a bit of difference between the
original capacitor values and the upgraded replacements provided, for
instance

Old New

47uF, 35V 100uF, 35V
2200uF, 10V 2200uF, 16V
330uF, 16V 470uF, 35

etc

My querstion is: do the upgraded capacitors only work together as a
set or can any one of them be replaced with the upgraded value?


In any combination you like.


OK, thanks.

In the latter case, a follow-up quesion would be how much variation in
capacitor value is permissible (presumably as long as it's higher)?


It's just a *maximum* voltage.


So in the third example above, where a 330uF 16V cap is replaced with
a 470uF, 35V cap, it wouldn't be advisable to exceed 35V for the
replacement?

  #4   Report Post  
Posted to sci.electronics.repair
external usenet poster
 
Posts: 2,770
Default Variation in usable capacitor ratings?



Art Deco wrote:

On Thu, 19 Oct 2006 14:53:37 +0100, Eeyore
wrote:
Art Deco wrote:

Hi everyone,

I've been upgrading a simple power supply in a satellite receiver
using a kit provided by a company selling spares.

I've noticed that there's quite a bit of difference between the
original capacitor values and the upgraded replacements provided, for
instance

Old New

47uF, 35V 100uF, 35V
2200uF, 10V 2200uF, 16V
330uF, 16V 470uF, 35

etc

My querstion is: do the upgraded capacitors only work together as a
set or can any one of them be replaced with the upgraded value?


In any combination you like.


OK, thanks.

In the latter case, a follow-up quesion would be how much variation in
capacitor value is permissible (presumably as long as it's higher)?


It's just a *maximum* voltage.


So in the third example above, where a 330uF 16V cap is replaced with
a 470uF, 35V cap, it wouldn't be advisable to exceed 35V for the
replacement?


It's not going to exceed 35V is it ? The voltage must be under 16V or the
original cap wouldn't have been suitable.

Graham


  #5   Report Post  
Posted to sci.electronics.repair
external usenet poster
 
Posts: 23
Default Variation in usable capacitor ratings?

On Fri, 20 Oct 2006 00:56:49 +0100, Eeyore
wrote:



Art Deco wrote:

On Thu, 19 Oct 2006 14:53:37 +0100, Eeyore
wrote:
Art Deco wrote:

Hi everyone,

I've been upgrading a simple power supply in a satellite receiver
using a kit provided by a company selling spares.

I've noticed that there's quite a bit of difference between the
original capacitor values and the upgraded replacements provided, for
instance

Old New

47uF, 35V 100uF, 35V
2200uF, 10V 2200uF, 16V
330uF, 16V 470uF, 35

etc

My querstion is: do the upgraded capacitors only work together as a
set or can any one of them be replaced with the upgraded value?

In any combination you like.


OK, thanks.

In the latter case, a follow-up quesion would be how much variation in
capacitor value is permissible (presumably as long as it's higher)?

It's just a *maximum* voltage.


So in the third example above, where a 330uF 16V cap is replaced with
a 470uF, 35V cap, it wouldn't be advisable to exceed 35V for the
replacement?


It's not going to exceed 35V is it ? The voltage must be under 16V or the
original cap wouldn't have been suitable.


I meant the voltage rating of the replacement capacitor.
Would it make a difference here if a 470uF 50V capacitor was used?



  #6   Report Post  
Posted to sci.electronics.repair
external usenet poster
 
Posts: 6,772
Default Variation in usable capacitor ratings?


"Art Deco" wrote in message
...
On Fri, 20 Oct 2006 00:56:49 +0100, Eeyore
wrote:



Art Deco wrote:

On Thu, 19 Oct 2006 14:53:37 +0100, Eeyore
wrote:
Art Deco wrote:

Hi everyone,

I've been upgrading a simple power supply in a satellite receiver
using a kit provided by a company selling spares.

I've noticed that there's quite a bit of difference between the
original capacitor values and the upgraded replacements provided, for
instance

Old New

47uF, 35V 100uF, 35V
2200uF, 10V 2200uF, 16V
330uF, 16V 470uF, 35

etc

My querstion is: do the upgraded capacitors only work together as a
set or can any one of them be replaced with the upgraded value?

In any combination you like.

OK, thanks.

In the latter case, a follow-up quesion would be how much variation
in
capacitor value is permissible (presumably as long as it's higher)?

It's just a *maximum* voltage.

So in the third example above, where a 330uF 16V cap is replaced with
a 470uF, 35V cap, it wouldn't be advisable to exceed 35V for the
replacement?


It's not going to exceed 35V is it ? The voltage must be under 16V or the
original cap wouldn't have been suitable.


I meant the voltage rating of the replacement capacitor.
Would it make a difference here if a 470uF 50V capacitor was used?

Almost certainly not, provided it fitted the board ok. But note that if it's
much bigger than the original part, that might bring it closer to some item
that runs hot, and this will shorten the life of the replacement by a
considerable factor...

Arfa


  #7   Report Post  
Posted to sci.electronics.repair
external usenet poster
 
Posts: 1,569
Default Variation in usable capacitor ratings?

On Fri, 20 Oct 2006 06:20:26 +0100, Art Deco put
finger to keyboard and composed:

On Fri, 20 Oct 2006 00:56:49 +0100, Eeyore
wrote:



Art Deco wrote:

On Thu, 19 Oct 2006 14:53:37 +0100, Eeyore
wrote:
Art Deco wrote:

Hi everyone,

I've been upgrading a simple power supply in a satellite receiver
using a kit provided by a company selling spares.

I've noticed that there's quite a bit of difference between the
original capacitor values and the upgraded replacements provided, for
instance

Old New

47uF, 35V 100uF, 35V
2200uF, 10V 2200uF, 16V
330uF, 16V 470uF, 35

etc

My querstion is: do the upgraded capacitors only work together as a
set or can any one of them be replaced with the upgraded value?

In any combination you like.

OK, thanks.

In the latter case, a follow-up quesion would be how much variation in
capacitor value is permissible (presumably as long as it's higher)?

It's just a *maximum* voltage.

So in the third example above, where a 330uF 16V cap is replaced with
a 470uF, 35V cap, it wouldn't be advisable to exceed 35V for the
replacement?


It's not going to exceed 35V is it ? The voltage must be under 16V or the
original cap wouldn't have been suitable.


I meant the voltage rating of the replacement capacitor.
Would it make a difference here if a 470uF 50V capacitor was used?


The only things I would be concerned about would be whether the higher
voltage types had higher leakage, which *may* effect some timing
applications, or whether the higher voltage types had higher ESR
values, which would result in poorer performance in switchmode supply
applications (as stated elsewhere in this thread).

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.
  #8   Report Post  
Posted to sci.electronics.repair
external usenet poster
 
Posts: 4
Default Variation in usable capacitor ratings?

I would personally replace all of them as a kit especially if they are being
used as timing or wave shaping. The higher capacitance rating when being
used as a filter is going to remove more ripple.

"Art Deco" wrote in message
...
Hi everyone,

I've been upgrading a simple power supply in a satellite receiver
using a kit provided by a company selling spares.

I've noticed that there's quite a bit of difference between the
original capacitor values and the upgraded replacements provided, for
instance

Old New

47uF, 35V 100uF, 35V
2200uF, 10V 2200uF, 16V
330uF, 16V 470uF, 35

etc

My querstion is: do the upgraded capacitors only work together as a
set or can any one of them be replaced with the upgraded value?

In the latter case, a follow-up quesion would be how much variation in
capacitor value is permissible (presumably as long as it's higher)?



  #9   Report Post  
Posted to sci.electronics.repair
external usenet poster
 
Posts: 4
Default Variation in usable capacitor ratings?

If I were doing it I would replace all as a set especially if they are being
used as wave shaping or timing caps. As a DC filter any capacitance
increase will usually remove more riple.

"Art Deco" wrote in message
...
Hi everyone,

I've been upgrading a simple power supply in a satellite receiver
using a kit provided by a company selling spares.

I've noticed that there's quite a bit of difference between the
original capacitor values and the upgraded replacements provided, for
instance

Old New

47uF, 35V 100uF, 35V
2200uF, 10V 2200uF, 16V
330uF, 16V 470uF, 35

etc

My querstion is: do the upgraded capacitors only work together as a
set or can any one of them be replaced with the upgraded value?

In the latter case, a follow-up quesion would be how much variation in
capacitor value is permissible (presumably as long as it's higher)?



  #10   Report Post  
Posted to sci.electronics.repair
external usenet poster
 
Posts: 28
Default Variation in usable capacitor ratings?


if there are switching supplies involved make the replacements are
rated for switching service or low/very low ESR

If I were doing it I would replace all as a set especially if they are being
used as wave shaping or timing caps. As a DC filter any capacitance
increase will usually remove more riple.

"Art Deco" wrote in message
...
Hi everyone,

I've been upgrading a simple power supply in a satellite receiver
using a kit provided by a company selling spares.

I've noticed that there's quite a bit of difference between the
original capacitor values and the upgraded replacements provided, for
instance

Old New

47uF, 35V 100uF, 35V
2200uF, 10V 2200uF, 16V
330uF, 16V 470uF, 35

etc

My querstion is: do the upgraded capacitors only work together as a
set or can any one of them be replaced with the upgraded value?

In the latter case, a follow-up quesion would be how much variation in
capacitor value is permissible (presumably as long as it's higher)?





  #11   Report Post  
Posted to sci.electronics.repair
external usenet poster
 
Posts: 9,560
Default Variation in usable capacitor ratings?

Art Deco wrote:

Hi everyone,

I've been upgrading a simple power supply in a satellite receiver
using a kit provided by a company selling spares.

I've noticed that there's quite a bit of difference between the
original capacitor values and the upgraded replacements provided, for
instance

Old New

47uF, 35V 100uF, 35V
2200uF, 10V 2200uF, 16V
330uF, 16V 470uF, 35

etc

My querstion is: do the upgraded capacitors only work together as a
set or can any one of them be replaced with the upgraded value?

In the latter case, a follow-up quesion would be how much variation in
capacitor value is permissible (presumably as long as it's higher)?


These largish value caps are usually used for smoothing and decoupling,
where values a bit bigger are a non issue. The voltage rating is the
max V the cap is rated to work with, so again replacing with the next
voltage up is a non issue.


NT

  #13   Report Post  
Posted to sci.electronics.repair
external usenet poster
 
Posts: 129
Default Variation in usable capacitor ratings?

In power supplies the capacitance values are usually not critical, so
anything up to 3 times the value is probably okay, actually, a good
thing.

The voltage rating can also be higher, up to 3 times higher is
perfectly okay. If you go above that, there's a chance the capacitor
will over time lose part of it's dielectric thickness, which will
increase the capacitance, which is harmless in 98% of the cases.

Reply
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Tek 465 trace brightness variation during sweep Al Schapira Electronics Repair 5 November 22nd 05 12:16 AM
Color variation with Honduran Mahogany Lars Stole Woodworking 7 January 24th 05 05:14 PM
moldy apple wood, usable? Adrian Mariano Woodworking 3 November 2nd 04 12:23 AM
Another variation on hourly rates UK diy 8 August 15th 03 01:17 AM
(another variation on) soundproofing party wall DP UK diy 0 August 14th 03 09:20 AM


All times are GMT +1. The time now is 05:20 PM.

Powered by vBulletin® Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 DIYbanter.
The comments are property of their posters.
 

About Us

"It's about DIY & home improvement"