Umbilicals

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I am building a phono-stage with separate power supply. I was planning on twisting 3 14 gauge wires together for the 6.3V heaters x 4 and the same for the B+ voltage. I was going to pass that thru a few feet of insulation from some Canare 4s11 star-quad cable I'd remove the conductors from. It occurred to me that maybe the 4S11 in it's star-quad form might suit the bill just as it is for the B+ of 250V and the heaters. Thoughts?
 
The Canare 46X series of cables is considered a great choice for DC umbilicals when used as a star-quad.

I'm not sure of your exact needs. How many conductors do you need in your umbilical, and what are the voltage and current requirements of for each conductor?

The 4S11 wired as star-quad would give you two 11 AWG wires, which is rated for 12 amps. It seems unlikely that your phono stage would need 12 amps of current. 4S6 has 20 AWG conductors, which gives you a pair of 17 AWG conductors and a rating of about 3 amps.
 

PRR

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> Is Canare 4S11 rated for 250V DC ?

Not rated for any voltage at all. {EDIT: it is *}
http://www.canare.com/UploadedDocuments/Star Quad - Speaker Cable.pdf

However it is 27mil of PVC. If it was 90mil it could be rated and tested for 5,000V.
https://www.anixter.com/en_us/resources/literature/wire-wisdom/insulation-levels.html
So the 27mil "should be good" for 1,500V.

Of course gaps skips or nicks in the PVC could greatly reduce this breakdown.

OTOH there will be two 27mil between conductors, making 3,000V. And reduced chance two defects will lay together.

{*} Small fine print: "Dielectric Strength = 500V AC / 1min."

If I believed it would breakdown at 501V for 61 seconds, I would fret about 250V. But I am pretty sure they know it is good for thousands of Volts, the market is not shopping for hi-Volt, and they do an occasional sample-check at a convenient 500V 1min (there's a standard test box for this).
 
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I'm almost ready to wire the two chassis together but I am realizing I don't see a way of safety grounding the two chassis together without a ground loop being created. The schematic shows the power supply outlined in red. I tried to indicate that there is an IEC connector with the safety ground next to it. Everything else is in the signal chassis. I will have two separate umbilicals with 4 conductors in each one (Canare 4S11 star-quad). All of the triangular ground symbols are to the ground bus and the flat-topped ground is to the chassis in the power supply.
The bus in the signal chassis will end up grounding to the turntable ground at the inputs.
Suggestions as how to tie the two chassis together would be appreciated.
 

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