Re: variacs in series

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <Mddeming-at-aol-dot-com>

In a message dated 10/23/02 6:50:23 PM Eastern Daylight Time, tesla-at-pupman-dot-com
writes:



>
> Original poster: "Matt Skidmore by way of Terry Fritz <twftesla-at-qwest-dot-net>"
> <fox-at-woozle-dot-org>
>
> speaking of pigs. it seems most coilers get the 14.4kv primaries. What
> would the effect be of using a 19.9kv primary at the same kva rating?is
> there any reason not to? i suspect going too high would create flashover
> and such. but it seems like going a bit higher with voltage would help
> compensate for drop due to ballasting or resistive loads. furthermore, it
> would require less capacitance, but need a cap rated for higher voltage,
> which, isn't really a problem. i just like to know what other people think
> on this :)



The 14.4 KV pigs have  ~20.4 KV(peak), while the 19.9 KVs have ~28.1 KV(peak).
Not only must the cap voltage ratings be higher, but also all wiring insulation
ratings, and corona losses on the TC primary side are higher. Quenching becomes
more of a problem as the voltage goes up, but gap losses are somewhat lower.
All TC work is a trade-off, and none of the changes seem to be very linear.
IMO, 7.7 KV is not "a bit higher voltage", but that depends on your reference
point.

$0.02 plain,
Matt D.