How to guarantee to lower noise- ground loops in your system

To Almarg,

Ok, so you proved my point, because your illustration only shows a 5 amp current draw on a 20 amp circuit breaker, there in not any way 5 amps could trip a normal 20 amp circuit breaker.  Your circuit illustration defective equipment  would have to be connected either to a ground fault receptacle or ground fault circuit breaker to be correct.  Never have I seen any ground fault equipment in any ones audio chain. Ground fault receptacles are made for wet locations, so be careful whenever you touch anything connected to a live circuit.  Wear non conductive shoes and only touch these items with one hand.  If you do however touch an energized piece of equipment while barefoot, briefly touch only with your right hand while standing on your right foot, but it is not safe practice. 

Every preamp or power amp that I own has a tiny fuse of no more than five amps.  My power conditioners have 20 amp circuit breakers that will trip if there was somehow a dead short pulling more than the specified 20 amps.  If however there was a 5 amp short like in the page 29 schematic there is no reason that it would not be safely discharged to ground. 

... your illustration only shows a 5 amp current draw on a 20 amp circuit breaker, there in not any way 5 amps could trip a normal 20 amp circuit breaker.

Yes, and that’s exactly the problem, as page 29 of the reference very clearly explains. In the event that a fault in a component causes the AC line voltage to come in contact with the metal chassis of the component the breaker is supposed to trip to prevent the possibility of someone being shocked or electrocuted. But with the grounding configuration described by you and on page 29 of the reference the breaker will not trip, leaving the chassis of the component energized at 120 volts (or whatever the line voltage is in the particular country). Thus defeating the fundamental purpose of the safety ground wiring.

If however there was a 5 amp short like in the page 29 schematic there is no reason that it would not be safely discharged to ground.

It would be discharged to ground, but not safely because the chassis of the component would continue to be electrified at the full AC line voltage. I’m not sure how that can be explained any more clearly than it is on page 29 of the reference.

Regards,
-- Al

I recently had awg 12 20 amp 4 wire dual grounds.installed , in retrospect less resistance 
I may go to awg 10 , seems many use and even awg 8
my question is I only have about 40 hours on my new dedicated line . The music seems a bit tipped up now on certain music . DoesAnyone have any experience with their own dedicated outlets and roughly how many hours for 
70ft of wiring to settle in, thank you.

vv32bl

Your response that me using a ground isolation receptacle and running the ground wire to an outside grounding rod does not sound logical that the circuit breaker could never trip.

I never said that the breaker would never trip. Please read more carefully. What I did note is that your grounding scheme was an NEC violation and created a dangerous situation (that could be lethal) where it would fail to trip under a specific circumstance.

... you do not even need a ground wire between your electrical meter and the first electrical panel in the house ...

You do in my town. In addition to NEC, you need to check local codes.

From your response above anyone that did not know any better would think that even with a dead short a non defective breaker would not trip.

I can’t imagine what I wrote that would lead you to that claim. You don’t quote the person to whom you respond, so it will remain a mystery, I guess.

... you do not even need a ground wire between your electrical meter and the first electrical panel in the house.

In a single phase [home] Ground [0v] is the transformer neutral and is wired from the meter to the panel Neutral. The line is tied to the transformer case and earthed. The Line goes above and below 0v.

NEC 250:
Equipment grounding must comply with the National Electric Code (NEC) Article 250. All non-current-carrying metal enclosures for electrical equipment or wiring must be grounded. Equipment grounding means a continuous copper conductor connected between the grounding electrode (rod/grid) connection, at the source transformer, and at each enclosure and equipment frame. This is the most critical concept in equipment grounding.

Line and Neutral are carried through to additional panels. Additional panels require the Earth Safety carried through. The Earth Safety is not Ground [0v] although it may be at 0v potential