[Boatanchors] Wanted: Source for multi-conductor cable

[Bill Weinel]

All,

If you plan to use this as tube type power supply cable, then there is one 
further caveat of which  you need to be aware..... 

Most multi-conductor cable sold today has an insulation breakdown voltage of 
only 300 VDC or less. This is inadequate to handle most tube type  MV DC power 
supplies (which typically run between 300 ~ 400 VDC.)  The use of this cable 
in a tube type power supply can lead to a short between conductors, which can 
destroy your power supply in the best case, and be a life safety shock hazard 
in the worst case.

If you do some searching on the internet, you can usually find a multi-
conductor cable that is up to the task. However, it is getting harder to 
locate and more expensive. 

I like to use 'wind-turbine rated' multi-conductor cable (which usually has a  
rated insulation breakdown voltage of around 1000 VDC.) I have also found some 
multi-conductor automotive cable which is useful for this purpose with an 
insulation breakdown voltage of around 600 VDC.

The important point is to always check the insulation breakdown voltage before 
using a multi-conductor cable as tube type power supply cabling.

73 Bill W4WHW
 

On Saturday, December 28, 2019 7:16:21 AM EST Rob Atkinson wrote:
> You don't need shielded cable for all of that, but CAT5 cable won't
> handle the current.  I'd make up a cable using copper THHN stranded
> house wiring of necessary gauge and cable tie them together.  I'd
> separate out the B+ and run that in shielded cables if it is high
> enough v., but if it is under 2 KV you can probably just use h.v.
> insulated wire and be fine.  You can get teflon insulated h.v. wire
> rated for pretty high v., such as 15 KV.  I'm not a fan of separate
> floor and table chassis with B+ wire between them anyway.   I prefer
> B+ runs to be inside something like a rack.   Don't waste time looking
> for a perfect solution; make up your own cable.
> 
> 73
> 
> Rob
> K5UJ
> 
> On Fri, Dec 27, 2019 at 10:52 PM D C _Mac_ Macdonald <k2gkk at hotmail.com> 
wrote:
> > Cable is needed to build power cable for tube type AM rigs.  AC power, 12V
> > filaments, hi and lo B+, bias, speaker, switching, etc.
> > 
> > 73 - Mac, K2GKK/5
> > (Since 30 Nov 53)
> > Oklahoma City, OK
> > USAF, Retired (61-81)
> > FAA, Retired (94-10)