RE: Testing cap. bank... (fwd)

[Steven Roys <sroys@xxxxxxxx>]

---------- Forwarded message ----------
Date: Wed, 6 Aug 2003 22:51:07 -0700
From: Dave Halliday <dh@xxxxxxxxxxxxxx>
To: 'High Voltage list' <hvlist@xxxxxxxxxx>
Subject: RE: Testing cap. bank... (fwd)

One of the caps probably has developed a low internal resistance.
Charge the bank up and leave it connected to the power supply for five
minutes. Disconnect the voltage and discharge the cap bank through a
resistor.  Feel each cap and see which one is warm.

Alternately, break the connection between the middle two caps.  Test
each bank of six.
The bank that fails, break the middle connection, test each bank of
three.

With two breaks, you have narrowed it down to one of three caps (unless
more are bad)

Some caps aren't rated for pulse discharge - the current you are drawing
may be weakening them and eventually, they will all need to be replaced.

Dave



> -----Original Message-----
> From: High Voltage list [mailto:hvlist@xxxxxxxxxx]
> Sent: Wednesday, August 06, 2003 7:18 AM
> To: hvlist@xxxxxxxxxx
> Subject: Testing cap. bank... (fwd)
>
>
> Original poster: Steven Roys <sroys@xxxxxxxx>
>
>
>
> ---------- Forwarded message ----------
> Date: Mon, 4 Aug 2003 15:12:05 -0500
> From: Shane Rusch <str@xxxxxxxx>
> To: hvlist@xxxxxxxxxx
> Subject: Testing cap. bank...
>
> Hey all, I was wondering if there is a easy way to weed out a
> bad cap in a parallal bank. My small wire exploder won't hold
> a charge. If I power up the bank and remove the input power
> it barely fires, if I power it up and fire it with the power
> left on it fires normally, don't like to do that although.
> The capacitance across the bank reads the same as always. The
> bank consists of 12 parallaled MO. caps. 5kv input through MO
> diode for approx 7 kv DC, 9 uf. total capacitance.
> Thank's   Shane.....
>
>
>