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Re: Why does running an NST on an async gap kill it?
Original poster: "colin.heath4 by way of Terry Fritz <teslalist@qwest.net>" <colin.heath4@ntlworld.com>
hi all,
i have experianced similar with diodes on a twin mot system with
voltage doubler.
if the safety gap fired a few times it would destroy the diodes
same stress different component.
cheers
colin
----- Original Message -----
From: Tesla list <tesla@pupman.com>
To: <tesla@pupman.com>
Sent: Monday, August 11, 2003 5:12 PM
Subject: RE: Why does running an NST on an async gap kill it?
> Original poster: "Lau, Gary by way of Terry Fritz <teslalist@qwest.net>"
<gary.lau@hp.com>
>
> Safety gaps should be applied only in parallel with the main gap and/or
NST
> secondary. Prior to firing, the main gap sees exactly the same voltage as
> the cap does. The capacitor does not ever see a voltage that exceeds what
> is across the main gap. So a safety gap across either the cap or the gap
> will be equally effective at clamping an overvoltage condition.
>
> But, the vital difference is that when the safety is across the gap,
should
> it fire, the energy from the cap will be transferred to the primary and
> secondary circuits, just like a main gap discharge, which is just fine.
If
> the gap were across the capacitor, there is nothing to limit the discharge
> current except the very low impedance of the arc, and the cap will see
VERY
> unhealthy discharge currents.
>
> Gary Lau
> MA, USA
>
> > Original poster: "Mudford, Chris by way of Terry Fritz
> <teslalist@qwest.net>" <chris.mudford@agresearch.co.nz>
> >
> > Hi Gerry
> >
> > In what configuration would one set a safety gap across an MMC
> > capacitor?
> >
> > Cheers, Chris (NZ)
>
>