Date: Wed, 17 Feb 2010 01:49:25 -0500
From: "Fuqua, Bill L" <wlfuqu00@uky.edu>
Subject: Re: [Amps] HV Fuses
I have thought a #30 wire or somewhat smaller wire was stretched inside a
grounded piece of copper
pipe such that there would be no discharge when HV was applied would be a
great fuse. This is because if
an arc in the tube would vaporize the wire and producing a plasma that would
short the B+ to
ground via the surrounding copper tube or pipe. Also, it would be easy to
replace.
73
Bill wa4lav
## This exactly what u don't want to do. You would simply coat the insides of
the copper tube with vapour
deposit. You would also grnd out the B+. We want the HV fuse to INTERUPT
the current... not
sustain it till something else blows up.
## Home made HV fuses, as larry suggest.. will work fb. I simply put one
fine strand between 2 x standoffs,
and when machine screws are tight... the fuse wire will be TAUT. OK, now you
wrap the exposed fuse wire
, loosely with 88 tape, and heat shrink tubing is even better. Fuse blows....
no mess, it's that simple.
### BTW.... SSON has loads of surplus BUSS HVU-3 HV fuses... $3-5
each.. depending on qty.
I bought a case load of em.. since they were the exact size I wanted. Each
fuse is still in it's individual
box, sealed. 5 kv / 50 ohm glitch R = 100 A of fault current. 100A
will blow that 3 A sand fuse
HVU-3.... very quickly... < 2 msecs.
## SSON also has a lot of other HV fuses available.. which might fit a
specific application.
later.... Jim VE7RF
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