Now there's what I was talking about Tony,
I love it when they can give you some solid answers. As usual the 1000V
caps have greater current capability due to their size.
NOTE: I also want to state that when changed to plain text the temps came
out 150C and 850C which I'm sure are 15 degrees C rise and 85 degrees C
ambient. If you were seeing the components rise 150 degrees C the solder
would be melting holding them in and they'd be drifting all over the place
in value.
While they didn't give you every value in their catalog you can see small
values have low current ability and large ones great. You can interpolate
the current ability for any values in between.
There is no shame in having 4 caps in parallel in a section of a filter to
get the correct capacitance and current carrying ability. Just remember the
larger caps carry that percentage larger current.
It is better to have 4 of the same value than two small caps and two larger
caps to share the RF current evenly.
Sincerely,
BOB DD
-----Original Message-----
From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com] On
Behalf Of ANTHONY JAPHA
Sent: Tuesday, December 05, 2006 12:57 PM
To: amps@contesting.com
Subject: [Amps] FW: Re: current ratings
Prompted by a few very helpful comments here on the reflector, I asked CDE
about the rf current ratings of some of their dipped mica caps. Here is
their response, which I hope is useful to others.
73,
Tony, N2UN
> [Original Message]
> From: Robert Sevigny <rsevigny@cde.com>
> To: <tjjapha@earthlink.net>
> Date: 12/5/2006 1:38:34 PM
> Subject: Re: current ratings
>
> Tony,
>
> Based on a 150C rise in an 850C ambient typical current ratings at 5 MHz
and
> up would be:
>
> CD15/500Vdc 100 pF .29 Amps
> CD15/500Vdc 470 pF 1.0 Amp
>
> CD19/500Vdc 1000 pF 2.1 Amp
> CD19/500Vdc 4700 pF 5.4 Amp
>
> CDV19/1000Vdc 100 pF .95 Amp
> CDV19/1000Vdc 1000 pF 3.0 Amp
> CDV19/1000Vdc 4700pF 6.5 Amp
>
> Bob Sevigny
> Senior Product Engineer
> Cornell Dubilier
> ----- Original Message -----
> From: "ANTHONY JAPHA" <tjjapha@earthlink.net>
> To: <rsevigny@cde.com>
> Sent: Monday, December 04, 2006 7:49 PM
> Subject: current ratings
>
>
> > Hi.
> > I'm using your CD15 and CD19 dipped micas in low pass filters to be
used
> > in
> > a 600 watt amplifier from 1.8 to 30 Mhz. What I'd like to know is if
> > their
> > are current rating considerations that need to be considered. I'm using
> > several 500 or 1000 volt capacitors in parallel, and believe that the
> > voltage ratings are sufficient. But what about current? The r.f.
current
> > may exceed 5A.
> >
> > Thank you very much.
> >
> > Tony Japha
> >
> > The information contained in this email message may be privileged,
> > confidential and protected from disclosure. If you are not the intended
> > recipient, any review, dissemination, distribution or copying is
strictly
> > prohibited. If you have received this email message in error, please
> > notify the sender by reply email and delete the message and any
> > attachments.
>
> The information contained in this email message may be privileged,
confidential and protected from disclosure. If you are not the intended
recipient, any review, dissemination, distribution or copying is strictly
prohibited. If you have received this email message in error, please notify
the sender by reply email and delete the message and any attachments.
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