[Amps] Coax for MHV connectors?

[Ian White GM3SEK]

Jim W7RY wrote:
>I use RG59 on mine. Works with 4KV and has been for years.

Same here. I suspect those voltage ratings are for square-cut open ends.


>
>-----Original Message-----
>From: Jim Barber
>Sent: Saturday, June 23, 2012 3:39 PM
>To: Amps at contesting.com
>Subject: [Amps] Coax for MHV connectors?
>
>I need to make up some MHV cables for a 4KV 2A max DC supply, (both B+
>and B-) and I made the mistake of looking up the voltage ratings for
>RG-58, RG-59 and LMR-240 cables, all commonly used with those connectors:
>
>RG-58        1900V
>RG-59        2300V
>LMR-240      1500V
>
>In a word, yikes! RG-59 has the highest rating, but I like it the least
>for exposed cables because of the solid center conductor
>
>The connectors are rated at 5KVDC, but what cable type? It seems like
>every time I think I know something... ?
>
>I'm tempted to give it up and machine my own bulkhead pass-throughs out
>of acrylic and use HV cable instead. In fact I would have already except
>I'd really like the cables to be detachable.
>

More important is that the connectors include their own chassis ground 
connection, and the coaxial cables will very probably short-circuit the 
supply if damaged.

What you must NOT do is allow a situation where an isolated amp chassis 
can be connected by a single HV+ lead with no ground return or HV-minus. 
(Welcome to the wonderful world of single-wire Millen connectors.)

And let's say it again: MHV connectors are a poor design which fails on 
too many important safety points. That is why it was necessary to invent 
the SHV connector.

Search the AMPS archives for "SHV" to see the rest of the story.


-- 

73 from Ian GM3SEK
http://www.ifwtech.co.uk/g3sek