[Amps] AL1500 cooling mod?

[rt_clay at bellsouth.net]

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 at 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 at contesting.com>
> To: <rt_clay at bellsouth.net>
> Cc: "Amps Amps" <amps at 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
> >
> >
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> > 
>