Wiring 2 outlets to 2 dedicated 20 amp circuits with a single 10/3 electrical wire.

@emergingsoul said:

The issue is trying to clarify why noise somehow is affecting the outlet in a manner that impacts performance of a system.

Maybe why noise from one circuit is affecting audio equipment connected to the other circuit of the multiwire branch circuit.

Lets try this again.

Just for an example.

Say on circuit Hot L1 conductor (coming from the electrical panel) you have a total connected 120V load of digital equipment of 2 amps.

Say on Hot L2 conductor (coming from the electrical panel) you have a 120V analog integrated amplifier load of 2 amps.

L1 = 2 amps.

L2 = 2 amps.

Load is Balanced on both L1 and L2.

Because of the way a multiwire branch circuit works Zero amps will return on the shared neutral conductor to the source).

So where is the circuit for the current (amps) to flow back to the panel, (source)?

The two connected loads are in series with one another. The shared neutral conductor from the panel is not involved.

One line diagram.

L1 conductor from panel >>> digital load >>> in series with >>> integrated amp >>> L2 conductor from panel.

The two series loads are being fed by 240V. (There is still a voltage drop across each load of 120V... 120V + 120V = 240V.)

So hopefully you can see the noise from the digital equipment, (if present), will be transferred to the primary winding of the power transformer in the integrated amp in the current as it passes through the primary winding back to the source on L2 conductor.

 

 

/ / / /

 

 

Note:

The source is actually the 120/240V split phase secondary winding of the Utility Power Company’s step down transformer.

.

jea48,
 

You say that, Zero amps will return on the shared neutral conductor to the source).

Not sure why this would be happening. And then from this point on in your response above I sort of lose an understanding of what you're saying.

But I'm really trying to follow. And I think for many it would be nice to know the rationale here as well, as this is a very profound issue.

@emergingsoul said:

You say that, Zero amps will return on the shared neutral conductor to the source).

Well it’s a fact... That is how a center tapped single phase 120/240 secondary winding of a step down transformer works.

Watch this video again. Make note the guy has the switch opened on the shared neutral conductor and the two light bulbs stay lit. The two light bulbs are in series with one another. At one point in the video he removes one of the bulbs, (breaks the series circuit), the other light bulb goes out. He reinstalls, (completes the circuit), and both bulbs are lit again.

 

@emergingsoul ,

Look at the first schematic diagram below.

Note: Load 1 and load 2 are identical. The loads are Balanced.

Note: The shared "neutral". 0 A (The shared neutral is not involved).

Load 1 and load 2 are in series with one another and are fed by 240V

 

 

Addition of neutral conductor allows loads to be individually driven.

 

 

Instead of a single 240 volt power supply, we use two 120 volt supplies (in phase with each other!) in series to produce 240 volts, then run a third wire to the connection point between the loads to handle the eventuality of one load opening. This is called a split-phase power system. Three smaller wires are still cheaper than the two wires needed with the simple parallel design, so we’re still ahead on efficiency. The astute observer will note that the neutral wire only has to carry the difference of current between the two loads back to the source. In the above case, with perfectly “balanced” loads consuming equal amounts of power, the neutral wire carries zero current.

Notice how the neutral wire is connected to earth ground at the power supply end. This is a common feature in power systems containing “neutral” wires, since grounding the neutral wire ensures the least possible voltage at any given time between any “hot” wire and earth ground.

An essential component to a split-phase power system is the dual AC voltage source. Fortunately, designing and building one is not difficult. Since most AC systems receive their power from a step-down transformer anyway (stepping voltage down from high distribution levels to a user-level voltage like 120 or 240), that transformer can be built with a center-tapped secondary winding: (Figure below)

 

American 120/240 Vac power is derived from a center tapped utility transformer.

https://www.ibiblio.org/kuphaldt/electricCircuits/AC/AC_10.html

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Note: See the two 120V rectangles?

Connect a 2A digital load across one and a 2A analog load across the other. 0 amps will return on the shared neutral. the two loads are in series and are fed by 240V

 

Jea48

Why are you talking about a step down transformer? this is a multi branch circuit involving 2 outlets, and a double pole breaker.

Appreciate all the commentary but my God, wtf?