Hi,

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

/Ruben


> At 20.09 2012.02.18, you wrote:
> >> Hello,
> >> I need a >=3D400V >=3D4.7uF pulse capacitor with a dV/dt rating >=3D20=
V/us.
> >>=20
> >> I can find them on Mouser, Digikey, etc.. e.g.:
> >> http://www.kemet.com/kemet/web/homepage/kechome.nsf/vapubfiles/F3294_P=
H
> >> 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 i=
s
> >> 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
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