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Lets talk dedicated lines

About a year ago I installed a dedicated 20 amp line for my system...and went as far as modding the whole power structure from the street transformer to my panel to my house...at some fairly major expense. The result was certainly an improvement for my system.
Recently i got to thinking that a lot of us have a system that utilizes the standard 15amp line that more than likely only supplies one other component in our rooms...and that is the lights. While lights can be noisy on the system, particularly if they are halogens, then this is a source of considerable hash and noise. However, since the only other thing shared by this line are the lights...and not the more power hungry grabbing stuff..like the refrigerator, or the Ac etc, then simply playing the system in the dark should essentially allow for a dedicated line effect to materialize on the gear that is attached to this line as well. The standard room convenience outlet( which is what we are talking about here) is 15 amp breaker protected and is only supplying the lights and the convenience outlet in a room....so ( assuming that this is the case--and the lights are the only thing supplied besides the outlet) what is the real advantage to the 'true' dedicated line ? Twenty amps is more than a lot of auto gear needs, so I doubt that is the issue...thoughts?
daveyf

Showing 2 responses by cleeds

cleeds
6,226 posts
 
danvignau
I use a dedicated 30 amp line to power my system, and it works great.
In many jurisdictions, that would require the use of 30A receptacles, which would in turn mean that you'd need to modify your equipment to have 30A plugs, or otherwise make some adapter for them. None of that is justified, imo. I think it's better to simply install multiple 20A lines, which can be improved by derating them.
... a 15 amp circuit uses 14 gauge wire, 20 amps 12 gauge, and 30 amp 10 gauge.
Not necessarily. There are variables such as the length of the run and whether the lines are in conduit, and there can be advantages to derating the line.  If you're in the US, always check local code as well as NEC.



cleeds
6,226 posts
 
Those convenience outlets are typically daisy-chained to other outlets, often in different rooms. That's not the equal of a dedicated line that runs straight from the receptacle back to the service panel, especially when you're trying to keep all the grounds at the same potential. 
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