Re: Maxwell 37667 pulse caps

["Tesla list" <tesla@xxxxxxxxxx>]

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

OK, I stand corrected as to the pulse rating. I now understand
there weak point is the voltage reversal rating.  If one were to
put 4 in series parallel, they would work fine, but 30nF, at $400
is a pretty steep price! If I could get some more (I have 5) at a
bargain price, I might think of making a kick-a$$ marx generator!
----- Original Message -----
From: "Tesla list" <tesla@xxxxxxxxxx>
To: <tesla@xxxxxxxxxx>
Sent: Wednesday, November 22, 2006 4:31 AM
Subject: Re: Maxwell 37667 pulse caps


> Original poster: "David Rieben" <drieben@xxxxxxxxxxxxxxx>
>
> Chip,
>
> I can't speak from personal experience on these caps, but
> it seems that the general consensus on these is that they
> are good for small to medium powered coils as long as you
> keep the primary circuit voltage <15 kV. There have been
> a few "early deaths" recorded with these caps when operated
> with 15 kV NSTs. Of course, keep in mind that most people
> overdrive their transformers with 140 volts in from their variac
> turned all the way up, so that's like 17.5 kV RMS input. The
> DC voltage rating of a commercial pulse cap should be at
> least 2.5x the maximum AC RMS voltage that it will be seeing,
> so running one of these with a 15 kV NST is pushing them on
> the "ragged edge" of their designed voltage limits.
> I don't think there's been many problems with these if they were
> ran with NSTs of 12 kV rating or less. I'm sure other with experience
> with these type of capacitors could comment on this. The 500 pps
> rating means just that - they are ated for 500 pps at their rated voltage.
> Most of the Maxwell 31xxx series capacitors are rated for just 1 pps,
> but most of the 37xxx series are rated between 100 and 1000 pps.
>
> David Rieben
>
>
> ----- Original Message -----
> From: "Tesla list" <tesla@xxxxxxxxxx>
> To: <tesla@xxxxxxxxxx>
> Sent: Tuesday, November 21, 2006 7:56 PM
> Subject: Re: Maxwell 37667 pulse caps
>
>
>  > Original poster: "Chip Ford" <chipford@xxxxxxxxxxxx>
>  >
>  > So you are saying even though Maxwell rates these caps at 500 PPS
(pulses
>  > per second), They are really one pulse per second caps? Does everyone
> agree?
>  > Has those that have used these caps been disappointed. Would I be
better
> off
>  > listing them on ebay and selling to the next sucker before I destroy
them?
>  >
>  > ----- Original Message -----
>  > From: "Tesla list" <tesla@xxxxxxxxxx>
>  > To: <tesla@xxxxxxxxxx>
>  > Sent: Tuesday, November 21, 2006 2:22 PM
>  > Subject: Maxwell 37667 pulse caps
>  >
>  >
>  >  > Original poster: "MIKE HARDY" <MHARDY@xxxxxxxxxx>
>  >  >
>  >  > Much has been descussed concerning the infamous 37667 maxwells.
>  >  > I think the general consensus is that these are 1 pulse/sec caps,
and
>  >  > therefore are a bad choice for coiling. Many list members report
>  >  > blowing them up. I bought 5 of them a few years ago in preparing
>  >  > for my big coils. I ran a pair in series with an NST powered coil,
>  >  > and had no problem, most likely because I way underrated them.
>  >  > Anyway, since another 'new' coiler just purchased a couple, it might
>  >  > be a good idea for Terry, to post a warning on the list index about
> these
>  >  > caps, so more of us don't unknowingly buy these, only to blow
>  >  > them up. What do others think?
>  >  >
>  >  >
>  >
>  >
>
>
>