Dedicated 20 amp circuit. 10/2 or 10/3?


Dedicated 20 amp circuit.  10/2 or 10/3? 

mmenasci

Lets think about why a dedicated line was conceived and what it is used to achieve. A dedicated line does the following in my mind:

1. Ensure that your audio system has more than enough power to handle a big amp pulling pulses of high current for bass notes and dynamic sections.

2. Ensure that the circuit is not shared with noisy items like washing machines etc with motors that start, lighting circuits that may have noisy dimmer switches, large resistive devices like hair dryers, irons, and heaters that can impact the shape of the sine wave, etc.

Note that we aren’t trying to protect the audio system from other things on the audio system. Exceptions might be: cheap power supplies for accessories such as ethernet switches, TV, TV streamers, wifi mesh hubs, etc. That is why I thought maybe you want to put in 2 lines, one for pure audio equipment and one for potentially noisy support stuff.

But I’m not convinced of the value of putting in dedicated line for each component. I guess it won’t hurt but I didn’t do it and I wouldn’t do it.

Effectively you’re moving the node where all the stuff ties together from the outlet behind your audio system to the breaker box, perhaps 50 ft away.

Jerry

@mmenasci 

Just to make sure I'm clear on what you mean regarding having all the circuits on the same "side".  The panel should have a diagram of how the circuits are connected.  The power from each 120 volt leg coming in is distributed using every other position on each side of the main box. This allows a 240 volt double pole breaker to pull from each side. 

One "side" is the red wires and one "side" is the black wires.  Each of these wires to neutral is 120V.  Red to black is how you get 240V.  

You should keep your load somewhat balanced on red and black but the entire audio system will not be a big enough load that it should be split. 

I put in one circuit from each side because it was convenient but not necessary.

Jerry

Another reason to have a circuit from each side would be if you found one side noisier than the other you could plug everything into the less noisy side.

Remember the threads of people trying to find mysterious noises?  switching to the other leg will usually solve that problem.