Kingrex said;
Interesting question. A little while back I had a project where I had to run 55 feet, 2 circuits in one pipe on the outside of a house. I spun the hot and neutral only on the 2 circuits and pulled the grounds loose in the pipe. I measured 0 mv between any of the neutral to grounds. I was quite surprised at this as I usually see maybe 5mv to 20mv. It has made me want to set up a test in my own system and measure whether it is best to leave the ground loose or twisted.
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I spun the hot and neutral only on the 2 circuits and pulled the grounds loose in the pipe.
I’ve posted that on this forum in the past. I first read about it, here:
An Overview of Audio System Grounding and Interfacing
Look at the chart/picture on page 35. Note, Twisted L-N beat out all the others. The EGC is pulled in the conduit along side the twisted pair.
A little while back I had a project where I had to run 55 feet, 2 circuits in one pipe on the outside of a house.
Best practices dictates a true dedicated branch circuit used for sensitive equipment does not share a conduit or cable assembly with other branch circuits.
I spun the hot and neutral only on the 2 circuits and pulled the grounds loose in the pipe.
NEC only requires one EGC sized for the largest circuit breaker handle amp rating of the circuits that share the same conduit.
