thin chinese capacitor syndrome

[Gareth Magennis]

I keep coming across this problem.

A (chinese made) power supply has blown its main caps.
Turns out said caps are allegedly made by Funtek or some other made up name.
I presume that the footprint of these caps are made as small as possible to
make the PCB as small as possible, height of caps is not so relevant.

Problem is nobody stocks those value caps in diameters that thin, so there
is no way to easily replace them as they will not physically fit the space.
The other problem is that the originals often blow up and need to be
replaced.
Maybe there's a reason these are not made so thin.


3 examples just in the last week are all 22mm diameter caps, where the only
ones I can find are 25mm and above.

4700uF 25v
680uF 200v
3300uF 63v



Gareth.

 

[Mark Zacharias]

"Gareth Magennis" <sound.service@btconnect.com> wrote in message
news:rVKLw.951996$T94.920012@fx26.am4...

I keep coming across this problem.

A (chinese made) power supply has blown its main caps.
Turns out said caps are allegedly made by Funtek or some other made up
name.
I presume that the footprint of these caps are made as small as possible
to make the PCB as small as possible, height of caps is not so relevant.

Problem is nobody stocks those value caps in diameters that thin, so there
is no way to easily replace them as they will not physically fit the
space.
The other problem is that the originals often blow up and need to be
replaced.
Maybe there's a reason these are not made so thin.


3 examples just in the last week are all 22mm diameter caps, where the
only ones I can find are 25mm and above.

4700uF 25v
680uF 200v
3300uF 63v



Gareth.

In time I would expect the thinner lower profile caps will become more
generally available. Meantime - you can often buy complete power supplies
(in the U.S. anyway) from second sources - Shopjimmy.com, even eBay. I'll
sometimes search the part number using Google shopping or Amazon's search
engine.

Sometimes even the prices are attractive. I've seen some Samsung power
boards going for less than 25.00.

Mark Z.

 

[Jeroni Paul]

I was in your situation and found the needed caps on ebay. Before that I tried to enlarge the teminals with wires to place the caps somewhere they would fit but it did not work due to the wires inductance. The supply voltage output dropped under load.

 

[mike]

On 3/11/2015 1:04 PM, Jeroni Paul wrote:

I was in your situation and found the needed caps on ebay. Before that I tried to enlarge the teminals with wires to place the caps somewhere they would fit but it did not work due to the wires inductance. The supply voltage output dropped under load.

There's certainly a limit to how long you can make the wires,
but I've had success in the past by putting a .1uF cap at the mounting
holes before adding longer wires...but longer was a quarter inch.

 

[N_Cook]

On 12/03/2015 17:22, mike wrote:

On 3/11/2015 1:04 PM, Jeroni Paul wrote:
I was in your situation and found the needed caps on ebay. Before that
I tried to enlarge the teminals with wires to place the caps somewhere
they would fit but it did not work due to the wires inductance. The
supply voltage output dropped under load.

There's certainly a limit to how long you can make the wires,
but I've had success in the past by putting a .1uF cap at the mounting
holes before adding longer wires...but longer was a quarter inch.

Or use 85 degree cap replacement and add a small fan in that area if the
space is available nearby