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What to tell my electrician

I am building out a dedicated listening room in a house we just purchased. There is a dedicated 200 amp breaker box for a hot tub we are getting rid of. So, I will have this breaker box deducted for a listening room. Assume i have a rig with mono blocks (ss), multichannel amp (ss) ,pre/pro, universal disc, dac, large led tv, cable box, distributed audio/video controller (control 4). The room is in the basement not very far from the breaker box (running lines would not be a problem). Also, the walls will be opened for the renovation so adding outlets and running wire not an issue.

I have read many of the threads on the subject here and am often confused by conflicting info and partial advice

So, what I would like is for any friends out here to put yourself in my shoes and imagine you are telling the electrician (who from what I have read will typically be amused and a bit confused by the Audiophile focus and perhaps not the best source of advice) what to do. So, would be great if the post is you imagining you are speaking to the electrician and saying. "ok, here is what I want you to do ......"

Assume I want to do it right and legally (so no non code separate grounds).
dangelod
sidssp
1,077 posts
 
Make sure your electrician follows the National Electrical Code (NEC). Don't do
things that will violate NEC even if someone tells you it may sound better.
Safety should always come first. Some electricians will do anything you tell
him. So make sure you ask him if what you want will violate NEC. If he is not
sure, hire someone else.
jea48
2,944 posts
 
.
NEC 2008
250.146 (D)

Quote:
Isolated Receptacles. Where installed for the reduction of electrical (electromagnetic interference) on the grounding circuit, a receptacle in which the grounding terminal is purposely insulated from the receptacle mounting means shall be permitted. The receptacle grounding terminal shall be connected to an insulated equipment grounding conductor run with the circuit conductors. This equipment grounding conductor shall be permitted to pass through one or more panelboards without a connection to the panelboard grounding terminal bar as permitted in 408.40, Exception, so as to terminate within the same building or structure directly at an equipment grounding conductor terminal of the applicable derived system or service. Where installed in accordance with the provisions of this section, this equipment grounding conductor shall also be permitted to pass through boxes, wireways, or other enclosures without being connected to such enclosures.

FPN: Use of an isolated equipment grounding conductor does not relieve the requirement for grounding the raceway system and outlet box.
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lak's avatar
lak
3,516 posts
 
One example of how to use two 5 KVA isolation transformers. These two isolation transformers go from my main AC panel to my sub-panel and power three different sound systems in my home.

http://cgim.audiogon.com/i/vs/s/f/1056415574.jpg
magfan
1,583 posts
 
There are whole-house surge protectors available. I'd install one.
These are not MOV type which have a lifetime, but rather another technology which doesn't wear out.
Cheap insurance.

For short runs, I'm sure that 4x20amp, 12 ga. will suffice.
Small isolation transformer is good for low current stuff. I use one as part of my Panamax power conditioner and it is great. and only a 400va unit.

Buy a 'Kill-a-Watt' power meter so you can measure voltage drop, current used and most importantly, Power Factor. The meter? about 25$ and is quiet the bargain. I use my as a tool, NOT for permanent installation.
tvad
9,467 posts
 
I'm biased against small isolation transformers plugged into outlets because I've yet to find one that didn't have mechanical hum coming from the transformer (OneAC, TrippLite, PowerVar).
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