Distribution System Overhead Line Configuration

[Fazlay]

Of a overhead distribution line, I have the Three Phase Geometrical Mean Spacing which is 58.371 Inches and Line to Neutral Spacing 48 Inches. Also have the sequence components.
Is there any way to find the Phase to Phase distance?

 

[davidbeach]

No. There are a multitude of configurations that would come up with the same Geometrical Mean. If you have some idea of the configuration you can narrow things down considerably.

 

[Fazlay]

Most Probably flat horizontal configuration

 

[KillBill7]

if you know the voltage level, you can make the educated guess. Most utilities have standard spacing for each voltage level.

 

[bacon4life]

GMD=[D1D2D3]^(1/3)
If you assume flat equal spacing, then you can assume: D1=D2=0.5*D3 resulting D1~=46 inches

Unfortunately, equal spacing is a bad assumption. Typically distribution either has 2 wires on one side of the pole and 1 wire on the other side of the pole, or the center phase is elevated by a foot or more on a peaker pin.

The Line to Neutral spacing could refer to:
The diagonal distance from the neutral to nearest phase
the vertical distance from the neutral to the bottom phase conductor
the vertical distance from the neutral to the geometric center of the phases
the diagonal distance from the neutral to the geometric center of the phases

Where did you get the GMD from? It could also be an average of various kind of construction owned by a utility, as utilities do not individually model the different impedances for corners, deadends, alleyarms, or other oddball configurations.

 

[crshears]

Although it is important to observe and comply with GMD minima, of greater importance to me is choosing an appropriate geometric configuration for your application...

Flat horizontal may not perform well in windy conditions, planar vertical won't handle either sleet jump or galloping conductors in winds with freezing rain, triangular dispo with neither vertical nor horizontal equilibrium between phases may be more unwieldy and expensive.

As Bill / waross is [ quite correctly! ] fond of saying, it depends.

CR

"As iron sharpens iron, so one person sharpens another." [Proverbs 27:17, NIV]