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

vv32bl

... I drove a new ground rod directly outside of my dedicated listening room, and connected an 8 gauge ground wire to an isolated 20 amp receptacle. That receptacle feeds my Pure Power 2000 a/c regenerator and also my APC S20 power conditioner. That isolated ground was the only ground wire for my stereo system, and did not connect to my electrical panel. It worked fine but I did not notice any great improvement in my sound.

That’s an obvious NEC violation and a potentially dangerous scheme, because a fault on the ground wouldn’t trip the breaker back at the panel. That’s why all grounds must be tied together with the neutral bus bar in the service panel.

To Cleeds,

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.

My first house did not even have any ground wires, and I blew plenty of fuses in that house.  To this day you do not even need a ground wire between your electrical meter and the first electrical panel in the house.  Although you do need to run a ground wire from the first panel to any other panels.

Ok, I mentioned running the neutral and ground wires from that receptacle to the exterior ground rod instead of going back to the electrical  panel.  There was a 120v circuit between the hot from the circuit breaker and ground wire that ran to the exterior ground rod.  Can you explain to me why the 20 amp circuit breaker would not trip if the circuits 20 amp breaker was overloaded, other than it being a defective breaker anyway.  It does not make any sense to me that a not defective 20 amp circuit breaker could pass more than the specified amperage just because the ground did not go to the neutral or ground buss bars, that's probably rated for well over 100 amps  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. You are in essence saying that it would be like not having the circuit breaker at all

Sure, I know that in the rare case that an overloaded 20 amp circuit breaker fails to trip you would hope that the panels 200 amp main breaker would trip before the wire from the 20 amp circuit started a fire.

Either having a defective breaker or like I said previously lightning could, and has started many fires.

The previous comment by Cleeds is 100% correct. For further explanation see page 29 of the following excellent paper, written by a distinguished expert on such matters:

https://centralindianaaes.files.wordpress.com/2012/09/indy-aes-2012-seminar-w-notes-v1-0.pdf

Regards,
-- Al

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