Re: ASRG blowing diodes

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "MIKE HARDY" <MHARDY@xxxxxxxxxx>

I took most of the advice of all the helpfull responses to my problem.
I rebuilt the supply as follows:

- using an 800V, 35 A bridge
- line filters on the line input, and the DC output
- 9,600 , 100V cap on bridge output, bypassed with MMC cap
- Varistor on each output leg to ground
- case grounded to line ground
- 5A fastblow fuse between bridge and xfmr output

It worked fine tonight, with a total runtime of about 1/2 hour, mothing
blew.
However I got some pretty good shocks from the case of the PS. As I
said, it's grounded to line ground. Any ideas here? I don't recall this
before.
----- Original Message -----
From: "Tesla list" <tesla@xxxxxxxxxx>
To: <tesla@xxxxxxxxxx>
Sent: Friday, July 07, 2006 6:43 AM
Subject: ASRG blowing diodes


> Original poster: "MIKE HARDY" <MHARDY@xxxxxxxxxx>
>
> I recently put a AR propeller gap on my 6", 4 kVA coil. It performs
> very well, Had some 9 foot ground strikes tonight. I run a 28V, 1.5A,
> 3600 rpm dc motor. Powered by a 6A variac into a 120 to 24 V 5A step
> down tranny into a full bridge rectifier (20 A, 200V). This should
> easilly run this, and it did for many hours. Varying the speed really
> does some interesting things to the character of the streamers! I
> decided to run the 24 line to the motor thru some flexible conduit
> that I grounded to RF ground (in case of streamer strikes). After a
> short time on the 4th, it poped the 2 A slowblow fuse, then stopped
> all together. I found that half the bridge shorted, overheating the
> tranny some. Replaced the bridge, ran it for 3 hours (not hooked to
> the coil) at nominal line voltage, and all was fine. Ran the coil
> again tonight, and after a few minutes it blew again! Oh by the way,
> I didn't ground the flex conduit this time. How do others deal with
> this, is my problem unique?
>
>
>
>