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Isolated ground for 20 amp

Hello,

I am planning to have three 20 amp circuits run from my panels into my music room which is right next to the basement where I got two 200 amp breaker boxes. 

To add an separate breaker box directly from the transformer, I was told it would be very expensive and it would make it commercial.

The electrician said, he can make a separate 100 amp panel and run 3 20 amp circuits. But the ground from the separated breaker box will be connected to the ground of one of the main panels. If the grounds are finally connected to the main panel, what is the point of having a separate 100 amp panel? I have quite a few 20 amp slots available in the main panels.

I am also reading about isolated ground. What does it exactly mean? I also read that, it is dangerous to have isolated ground and regular ground next to each other, as each can have a different potential and it can kill people when touched simultaneously.

I also read that, all grounds have to be connected to each other as a safety code. If that is the case, how does isolated ground actually isolate?

Also, I want to connect my components directly to the three 20 amp lines, so I can save cost on conditioners. How do conditioners work? some say they impair sound.

My components are: Reed Muse 3c, Ypsilon MC26L SUT, Ypsilon VPS100, Cary SLP05, Cary DMS600, Cary CAD 211FE monoblocks, KEF Blades

Sorry, any guidance is hugely appreciated.
kanchi647
erik_squires
16,069 posts
 
All grounds in a home must be bonded together and come to the neutral at exactly one point.  Everything else is a danger to life and property.

However, you can run a ground rod loop. That is, you can put in more ground rods near your listening location, and loop them in.  Totally fine so long as the above remains true.

The only thing dedicated lines will do is reduce the noise you might get from other in-home sources.  However, it's 50/50.  The better your wiring, the closer you are to the transformer, the more outside noise you can bring in.

I wrote about the need for conditioners extensively here:

https://inatinear.blogspot.com/2019/04/power-management-for-frugal-audiophiles.html

Best,

Erik
Ag insider logo xs@2x
cleeds
5,950 posts
 
erik_squires
The only thing dedicated lines will do is reduce the noise you might get from other in-home sources.
I think the greatest benefit from dedicated lines is the virtual elimination of voltage drop. That might matter less to you if you aren't using large amplifiers.
millercarbon's avatar
millercarbon
12,531 posts
 
Pains me to see so many spending so much for so little. Do not add a panel. Total waste of time and money. Run one line. Do a search. Read my comments. Including the ones with this link where you will want to pay special attention to what Michael Fremer says at 15:50.  https://ultimist.com/video/2018/07/21/michael-fremers-listening-room/
gs5556
1,234 posts
 
Receptacles with isolated grounds are still grounded. The ground is isolated from the grounding system downstream of the panel. For example, if you install a receptacle to a metal receptacle box you tap from another circuit, the grounds are common to all outlets on that circuit through the boxes and wiring. An isolated ground receptacle has insulators on the ears which insulates (isolates) the receptacle from the box. The receptacle is then grounded by the green wire attached to the screw on the receptacle and the wire is run directly to the ground bus of the panel and does not join any other circuit grounds.

If you use romex wire and plastic boxes, the ground scheme is almost the same. Since the plastic box is non-conductive, you are required to ground the green wire to the receptacle screw. If that circuit happens to be dedicated to that receptacle, it becomes an "isolated ground" receptacle by default.
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