[Top] [All Lists]

Re: [Amps] Oil-caps delating 2/3 ratings?

Subject: Re: [Amps] Oil-caps delating 2/3 ratings?
Date: Thu, 6 Mar 2008 11:48:12 EST
List-post: <">>
Han, I have lost two similar capacitors running at about 3500vdc over the  
years. Both of my capacitors were purchased from Peter Dahl Co and were rated  
for 5000vdc working voltage. I came to the conclusion that oil type capacitor  
ratings are not as robust as electrolytic type ratings.
I think the failure mode has to do with ripple current and associated  
heating. Both failures happened while calling cq for long periods in an EME  
Gerald K5GW
In a message dated 3/6/2008 4:03:05 A.M. Central Standard Time, writes:

Recently  an old man told me that all of the caps are energy storage jobs
and they  are usually derated for continuous duty to about 2/3 rating.
I thank him  very much.

I am using cheap 32uF 4500V GE non-pcb caps.
Should I use  it at 3000V maximum? 
Fortunately I am using this potential level  now.
If someone use 16uF 7500V Arioso caps like Henry,
maximum working  voltage should be 5000V?

Would you please tell me the reason for the  "2/3 derating" 
practically when using them for our linear amps?

For  a long time I had a question why GE had not indicate working 
voltage and  test voltage but only "4500V".

Additionally anyone did a  destructive/non-destructive test on it?
Seemingly they are sustainable at  5kV, but if the number 2/3 work
their life should be very short.

de  Han JE1BMJ
Amps mailing  list

**************It's Tax Time! Get tips, forms, and advice on AOL Money & 
Finance.      (
Amps mailing list

<Prev in Thread] Current Thread [Next in Thread>