Jellybean electrolytic capacitors

[Joerg]

Can you provide us with a nice photo?

I almost knew you'd ask but, unfortunately not. It always happened out
of the blue. Once the fire alarm even started blaring.

This one has the aftermath, last picture:

http://www.empf.org/empfasis/mar05/catafailure305.htm

 

[Fred Bartoli]

Winfield Hill a écrit :

Hmm. Anybody else?


Yes indeed!

I've bought quite a few organic electrolyte parts for
test, plus three values of OS-CONs we got as samples
from their distributor, Capacitors Plus. But I wonder
how hard they normally are to get in small quantities,
since they aren't available from regular distributors?

Farnell carries them.

 

[Tim Williams]

Get the Mythbusters to blow up some electronics. It's a pretty sure thing
to make tants go off, so it'd be a cinch to catch it on their highspeed.
Now you just need a mythscuse to bring it up...hmm...

Tim

 

[Tim Williams]

I would be interested in seeing some measurements on those audiophool /
botique parts. Elna Cerafine, Black Gate, and a smattering of other types
are "audiophile approved" electrolytics (if you can imagine such a thing).
You could also explore the silly film caps (Auricap, etc.), but I don't
mind that as much.

Tim

 

[[email protected]]

Hi,

Panasonic NHG is great, and M series seem common.

When it comes to availability, whatever is at Digikey and Mouser or
the like is about it.

It would be interesting to see the results of at least one bad
audiophile cap, which is also available at digikey and called the
silmic II.

I hope you'll do a similar chart on low ESR electrolytics.

Looking forward to the next edition.

Cheers
Chris

 

[Harry Dellamano]

On Wed, 21 Nov 2007 19:55:25 GMT, Joerg


Buy better lams.

We had one transformer, not too big, 10 pounds maybe, that ran warm
and, if you teased the power switch, would make the wiring in the
walls thump audibly at turnon. We measured close to 1000 amps peak
current. It would also fry varnish at 130 volts.

Here's the transformer plot for Win...

http://img66.imageshack.us/my.php?image=xfmrscatterbq5.jpg

This graph was really hard to shoot... terrible Moire' effects.

John

Thanks, JL, that goes up on my wall. Got the equations that fits the
graph?
Cheers,
Harry

 

[Winfield]

We're not going to teach ac-power-line design, excepting
SMPS types. But we may teach signal-transformer design,
including high-frequency power stuff.

Buy better lams.

What're lams, laminations? You mean buy transformers?

We had one transformer, not too big, 10 pounds maybe, that ran warm
and, if you teased the power switch, would make the wiring in the
walls thump audibly at turnon. We measured close to 1000 amps peak
current. It would also fry varnish at 130 volts.

Here's the transformer plot for Win...
http://img66.imageshack.us/my.php?image=xfmrscatterbq5.jpg
This graph was really hard to shoot... terrible Moire' effects.

John, thanks very much, that's a spectacular graph,
with a 1000:1 VA range and an over 200:1 weight range.
What kind of transformers (specific types?) did you
measure for the data points? Do you still have the
raw data? We're using Igor for our graph plotting.

 

[Winfield]

Winfield Hill a écrit :




Farnell carries them.

Good lead, then I can get them through Newark.

 

[Winfield]

I would be interested in seeing some measurements on those audiophool
/ botique parts. Elna Cerafine, Black Gate, and a smattering of other
types are "audiophile approved" electrolytics (if you can imagine such
a thing). You could also explore the silly film caps (Auricap, etc.),
but I don't mind that as much.

I'm willing to go for a few, but I imagine they're
so overpriced that could be an issue. If you'll
suggest a few candidates and provide link info,
I'll pursue them and try to include the detailed
measurements. I'll also post my measurements.

 

[John Larkin]

We're not going to teach ac-power-line design, excepting
SMPS types. But we may teach signal-transformer design,
including high-frequency power stuff.


What're lams, laminations? You mean buy transformers?

Yeah, laminations. Transformer companies tend to use really cheap
silicon steel and just skim the edge of saturation. If you get in
trouble on saturation, they can usually go to some better material and
get decent margins in the same physical size.

John, thanks very much, that's a spectacular graph,
with a 1000:1 VA range and an over 200:1 weight range.
What kind of transformers (specific types?) did you
measure for the data points? Do you still have the
raw data? We're using Igor for our graph plotting.

I did a few custom transformers that we use, and looked up some others
in catalogs, just to get an idea of the slopes.

I still like to use graph paper. You just whack the little dots
down... no typing numbers. There is no raw data, you just plot it.

John

 

[Eeyore]

We're not going to teach ac-power-line design,

You ought to really. The sheer number of misconceptions people have about how to
do it always amazes me.

Graham

 

[Jeff Liebermann]

Can you provide us with a nice photo?

See:
<http://802.11junk.com/jeffl/pics/drivel/Blown Power Supply.jpg>
It's not a flamed out tantalum, but an example of what happens when a
cheapo ATX power supply goes over-voltage. The paper mess was from
two electrolytic capacitors. The charred PBC near the purple
electrolytic is probably what inspired the over-voltage. Incidentally,
literally every board and drive in the computer was also blown.

Incidentally, speaking of tantalums, have you run into any with sky
high ESR? I have. See the description next to the photo of the two
tantalum caps at:
<http://ludens.cl/Electron/esr/esr.html>

My favorite capacitor experiment was (someone) dropping a metal bar
across the terminals of an oil drum capacitor. I forgot the
capacitance, but the voltage rating was at least 10Kv. A bank of
these were used to vaporize a wire to fire off a big Hi-V switch. It
took 1 or 2 days to charge the oil drum capacitor, and a few
milliseconds to temporarily wreck my hearing, spray molten aluminum
slag everywhere, and panic everyone in the building. Sorry, no photos
of the devastation.

There are about 30 assorted videos on YouTube under "exploding
capacitor" and "capacitor bomb".
<http://www.youtube.com/results?search_query=exploding+capacitor>
All are electrolytics. No tantalums. Well, time to make an exploding
tantalum video.

This has nothing to do with the discussion, but is kinda interesting.
Exploding a potato with a defibrillator cazapitor:
<

>
Same thing with apples:
<

>

 

[Winfield]

Joerg


http://img144.imageshack.us/my.php?image=bangvf0.jpg

John

I've seen more than my share of those looking that
bad or worse. In more than one instance we had to
replace the entire set of caps on the pcb. I've had
not only the teardrops, but multiple smt tantalums
too, 50V parts being used as 5V bypass, kablowee!
That was on a pcb in our $750,000 NMR machine.

 

[Robert Latest]

For example, I used to get
lots of Panasonic HFS series parts - reasonably-low
esr, not too expensive,

I seem to be using Panasonic's FK series a lot, if for no other reason
than that they are cheaply available from Farnell.

robert

 

[Robert Latest]

Thanks, JL, that goes up on my wall. Got the equations that fits the
graph?

C'mon, that's straight lines on a log-log plot. The equations can be left as
an exercise to the reader.

robert

 

[John Larkin]

I've seen more than my share of those looking that
bad or worse. In more than one instance we had to
replace the entire set of caps on the pcb. I've had
not only the teardrops, but multiple smt tantalums
too, 50V parts being used as 5V bypass, kablowee!
That was on a pcb in our $750,000 NMR machine.

We did an analysis of field returns on our VME modules. We're besting
Bellcore mtbf calculations by about 3:1, and half the failures were
tantalum caps.

We rarely use them any more. That's too bad, because they are like
Saabs: great gadgets, between fires.


John

 

[Harry Dellamano]

C'mon, that's straight lines on a log-log plot. The equations can be left
as
an exercise to the reader.

robert

Gotcha, Y= mX+b
Thanks,
Harry

 

[qrk]

Really? I've just been measuring the radial-lead
parts from my drawers, and was planning on ordering
only that style, is that a mistake?

If my assertion is correct, it would be a good side note. However,
it's getting harder to find axial electrolytics these days so it might
not be necessary. United Chemi-Con and Panasonic don't make them
anymore. Digikey only carries BC Components for axial Al
electrolytics. In the late 80s, I was looking for electrolytics for
high current pulse applications. The esr difference between radial and
axial was quite visible.

Forgot to add my favorite cap into the fray. Although not jellybean,
they aren't much more expensive.
United Chemi-Con KZE series. DigiKey and Mouser stocks these parts.
These are low impedance 105 deg parts. I use these for high current
pulse applications and replacing bum capacitors in modern electonics
with switching supplies that die in a year or two.

 

[Don Lancaster]

If my assertion is correct, it would be a good side note. However,
it's getting harder to find axial electrolytics these days so it might
not be necessary. United Chemi-Con and Panasonic don't make them
anymore. Digikey only carries BC Components for axial Al
electrolytics. In the late 80s, I was looking for electrolytics for
high current pulse applications. The esr difference between radial and
axial was quite visible.

Forgot to add my favorite cap into the fray. Although not jellybean,
they aren't much more expensive.
United Chemi-Con KZE series. DigiKey and Mouser stocks these parts.
These are low impedance 105 deg parts. I use these for high current
pulse applications and replacing bum capacitors in modern electonics
with switching supplies that die in a year or two.

We have zillions of these at
http://search.ebay.com/_W0QQfgtpZ1QQfrppZ100QQsassZabeja

--
Many thanks,

Don Lancaster voice phone: (928)428-4073
Synergetics 3860 West First Street Box 809 Thatcher, AZ 85552
rss: http://www.tinaja.com/whtnu.xml email: [email protected]

Please visit my GURU's LAIR web site at http://www.tinaja.com

 

[Robert Baer]

What do you think is a good general-purpose low-cost
versatile jellybean aluminum electrolytic capacitor line?
I'm looking for a manufacturer and specific product line.
When I say versatile, I mean available in a wide range of
part values and operating voltages, and physical sizes.

Not necessarily in order: Xicon, Panasonic, Nichicon.