At 09.59 2012.02.19, you wrote:
>Hi,
>
>I can just say that I am using a PHE426 metallized polypropylene=20
>capacitor in a=20
>CDI like circuit to produce ionized air for electrostatic discharging.=20
>Although=20
>mine is only 330nF/250V=3D, they have been working very well in around=20
>1000 units=20
>so far and still counting (there are actually two in one unit, one for=20
>positive=20
>charge and one for negative). The capacitors are charged and discharged ar=
ound=20
>9000 times per second with an alternation frequency of between 1.4Hz to 10=
Hz=20
>(both are not working at the same time).

Thanks. If I may ask, to what max DC voltage do you charge these 250V units=
?

I assume that charging to the rated voltage is safe, but the doubt is there=
..
Of course at ambient temperature.

Cheers,
Mario


>
>/Ruben
>
>
>> At 20.09 2012.02.18, you wrote:
>> >> Hello,
>> >> I need a >=3D400V >=3D4.7uF pulse capacitor with a dV/dt rating >=3D2=
0V/us.
>> >>=20
>> >> I can find them on Mouser, Digikey, etc.. e.g.:
>> >> http://www.kemet.com/kemet/web/homepage/kechome.nsf/vapubfiles/F3294_=
PH
>> >> E426.pdf/$file/F3294_PHE426.pdf
>> >>=20
>> >> But they are all too big/bulky!!
>> >>=20
>> >> What should I look for? Is there a different technology than
>> >> polypropylene, still suitable for >=3D20V/us pulse applications, and =
is
>> >> not as bulky as those caps?
>> >>=20
>> >> Even half the size would already be a big win for me.
>> >
>> >What you are have found is a capacitor that is rated for continuous=20
>> >connection to 230V mains for use in mains filters or as motor run=20
>> >capacitors and the like, often referred to as X2 rated, or something=20
>> >like that. I don't think you will find anything else that will do what=
=20
>> >you want.=20
>> >
>> >Note also that you don't quote a dI/dt rating - but this will probably=
=20
>> >be the rating that will bite you in the backside. It is an easy rating=
=20
>> >to ignore, and will often result in shorted capacitors, a familiar=20
>> >form of failure for anyone that attempted to use the old Philips=20
>> >'lollipop' polycarbonate capacitors in items like capacitor discharge=20
>> >ignition systems.
>>=20
>
>
>
>=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
>Ruben J=F6nsson
>AB Liros Electronic
>Box 9124
>200 39 Malm=F6 Sweden
>Tel +46 40142078
>ruben@rjjournal.net
>=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
>
>--=20
>http://www.piclist.com PIC/SX FAQ & list archive
>View/change your membership options at
>http://mailman.mit.edu/mailman/listinfo/piclist

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