While the specified operating temp may indeed be that high, the operating life
of the cap decreases with increasing temperature.
I found the following document,
http://industrial.rell.com/pdfs/IPG_AN_appguide.pdf
which claims on page 15 "For capacitors operating at moderate temperature the
operating life doubles for each 10 deg C that operating temperature is reduced."
Tor
N4OGW
-------------- Original message ----------------------
From: "jeremy-ca" <km1h@jeremy.mv.com>
>
> Why would the electrolytics in the AL-1500 require any special airflow since
> they are 105* C computer grade and meant to operate in a warm enviroment?
> You once claimed that those caps were a special order of the highest
> quality.
>
> Amp Supply used the same filters (or a close approximation) and Ive yet to
> hear of a bad one even tho many are over 20 years old.
>
> Carl
> KM1H
>
>
> ----- Original Message -----
> From: "Tom Rauch" <w8ji@contesting.com>
> To: <rt_clay@bellsouth.net>
> Cc: "Amps Amps" <amps@contesting.com>
> Sent: Thursday, September 06, 2007 12:29 PM
> Subject: Re: [Amps] AL1500 cooling mod?
>
>
> >
> >> Any opinions on this modification to the AL1500?
> >>
> >> http://techcomnetworks.com/ve2jka/forum/showthread.php?t=177
> >
> >
> > I certainly would never do that mod. First, that series of
> > amps takes cool air in across the electrolytics and then
> > across the transformer. His mod will kill the airflow across
> > the sensitive electrolytics.
> >
> > Second the airflow out through just a few top holes will be
> > far too restricted. The airflow is already set at the
> > minimum possible airflow to keep tube seals below rated
> > temperature at the rated duty cycle.
> >
> > My bet is he never measured anything and is just "guessing"
> > things are OK.
> >
> > 73 Tom
> >
> >
> > _______________________________________________
> > Amps mailing list
> > Amps@contesting.com
> > http://lists.contesting.com/mailman/listinfo/amps
> >
>
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