Your Favorite AC Outlets

From Wikipedia

Isolated Ground Outlet

Good listening

Peter

I use the gold plated Furutek outlets and find them to be a nice upgrade over stock outlets. You should call Cable Co. They probably carry every outlet on the market. They'll give you honest recommendations, as well.

Peter, thanks for providing the link. Mofi, as the link indicates an isolated ground receptacle has no internal connection between the safety ground contacts of its two outlets and any surrounding metal structure, or conduit if present. In a home environment the safety ground contacts would typically be connected through an insulated wire to the central grounding point at the service panel, where safety grounds, AC neutrals, and earth ground are all connected together. A separate path to that ground point is required for the surrounding metal and the junction box, typically via conduit.

So the AC safety ground connections for the equipment are not truly isolated, of course, as that would be a safety hazard. What is changed with respect to a conventional outlet is just the route by which the equipment safety grounds are connected to ground, with the goal being a reduction of the amount of noise that is coupled into the equipment.

There's lots of info (and also lots of confusion) on the web about isolated ground receptacles and wiring. One brief excerpt from this paper by Bill Whitlock of Jensen Transformers, who as you may be aware is a renowned expert on such matters as they apply to audio:

So-called “technical” or “isolated” grounding schemes can sometimes reduce electrical noise in the safety ground system. It is most applicable in situations where conduit may come in contact with building steel, water pipes, gas pipes, or other structures which may be grounded and carrying noisy currents. Special insulated ground or "IG" outlets (generally orange in color) are used, which intentionally insulate the green safety ground terminal from their mounting yokes or saddles. Therefore, safety grounding is not provided by the "J-box" and conduit, but by a separate insulated green wire which must be routed back to the electrical panel alongside the white and black circuit conductors to keep inductance low. Most often, wiring is not "daisy-chained" to outlets on the same branch circuit, so noisy leakage current from one device has less coupling to others on the same branch circuit. However, inductive coupling from phase conductors to the ground conductor (a major source of ground voltage differences between outlets) is not reduced.

Thanks for the implicit compliment, btw, but I am by no means the leading expert here on electrician-type matters. That would be Jea48 (Jim); perhaps he'll see this thread and comment further.

Best regards,
-- Al

http://www.voodoocable.net/VAPO.htm

Al...as usual your comments are highly informative and greatly appreciated! I'm still kinda confused about the "outlet" part of this.

I have dedicated 20 amp lines that run from my service box to the outlet in the wall. So do I or don't I have isolated grounds? The outlet is only wired to themselves, (i.e. no other outlets are in series with them). There are also no metal conduits or anything else involved. The wire runs straight from the box to the outlet which are Porter Ports.

I guess I have never heard this termed as "isolated grounds" before. I have absolutely no noise from my setup.

BTW, you are "my" expert in everything electrical as related to audio...don't sell yourself short :-)

Thanks again!