Re: Potting Diode Strings - yes!

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

Original poster: "Kevin Ottalini by way of Terry Fritz <twftesla-at-qwest-dot-net>" <ottalini-at-mindspring-dot-com>

Rick:
        My answer was a bit too long and lost the point I guess ...

The answer is yes you can use glyptol or corona dope to
fix a string of diode assuming you give them a good coating
(or several) and have them mechanically mounted so they
don't flex.

As far as replacing one diode in the string ... I doubt that
it will be worth the effort since how will you know which one
is bad when they are all coated? (scrape, test, recoat, arg)

Corona is unfortunately not the only enemy though, but
any sort of accidental cause of arc, so enclosing the
string in a plastic housing or tube is very highly
recommended once you know it works ok.

For my work, I usually worry about uA of leakage in the
2kv-60kv range since 10uA of leakage at say 20kv is
200mw ... and that can double the power consumption
for my typical application!  Corona dope just isn't good
enough for that level of application.

For TC work where we're talking about 1kw to 4kw
the power loss isn't important, but the presence of
all those free charged ions floating around can be a
problem since DC charges tend to accumulate on
surfaces and can lead to break down and arc over.

Kevin

----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Thursday, March 21, 2002 3:36 PM
Subject: Re: Potting Diode Strings - yes!


> Original poster: "PotLuck by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<potluck-at-xmission-dot-com>
>
> Hi Kevin, all,
>
> I suppose my question was a bit misleading. If corona is the enemy here
then
> could corona dope be used instead of potting the diodes? I've not used it,
> nor have I seen it mentioned much, if at all, on the list. If it can be
used
> instead of potting then it would probably be a lot easier to "service" a
> string if a diode went bad?
>
> Rick W.
> Salt Lake City
>