Why is this Mainline Neutral Fused? (SoCal Edison)

[samgillis]

I live in SoCal and believe I am seeing the mainline neutral on poles getting its own fused cutout.

While I’ve heard there is a lot of ungrounded delta in this area, I’ve also been told by an Edison worker that there is 4 wire wye distribution, as well.

I know the pictures aren’t the easiest to see, but the one with the pole xformer shows the two outer lines being tapped to feed the primaries, and when I went further down the road and found where the lines were dropped underground to go into a neighborhood you can see that the two outer lines have red and white tape on them, respectively.

The white tape tells me that must be the mainline neutral, right? But why would they fuse it? Could it be that it’s not a MGN distribution and they only ground at the xformers, making the mainline neutral have a high enough voltage to ground to warrant fusing it (since the wire distance back to the sub xformer is quite far)?

 

[Dsg319]

Could be a phase conductor just tapped white? I know I’ve seen some poco distribution lines phased white even though it was an ungrounded conductor.

Not sure how there phasing schemes are.

 

[samgillis]

Can the color codes be different for distribution voltages? And what would the fourth wire be, then? A lightning wire?

 

[don_resqcapt19]

I live in SoCal and believe I am seeing the mainline neutral on poles getting its own fused cutout.

While I’ve heard there is a lot of ungrounded delta in this area, I’ve also been told by an Edison worker that there is 4 wire wye distribution, as well.

I know the pictures aren’t the easiest to see, but the one with the pole xformer shows the two outer lines being tapped to feed the primaries, and when I went further down the road and found where the lines were dropped underground to go into a neighborhood you can see that the two outer lines have red and white tape on them, respectively.

The white tape tells me that must be the mainline neutral, right? But why would they fuse it? Could it be that it’s not a MGN distribution and they only ground at the xformers, making the mainline neutral have a high enough voltage to ground to warrant fusing it (since the wire distance back to the sub xformer is quite far)?

Not on the utility side.

 

[mtnelect]

Not on the utility side.

I am in SCE (Southern California Edison) territory ... they are upgrading all their systems 4160 primaries and replacing all their poles. And fusing all the primary branches at each transformer.
Also, the primary wires are now insulated.

This is because of wildfire prevention.

 

[LarryFine]

POCOs do not follow any color standards. They only need to tell them apart.

 

[Birken Vogt]

POCO neutrals are always grounded at multiple places along the way. And often have smaller insulators. They never have cutouts or switches. Always solidly continue through where a switch might be. White must just be one of their phase colors.

 

[BarryO]

POCO neutrals are always grounded at multiple places along the way. And often have smaller insulators. They never have cutouts or switches. Always solidly continue through where a switch might be. White must just be one of their phase colors.

Yep. Neutrals are never fused and are grounded at multiple places. When working on phase conductors that are believed to be de-energized, they are shorted by line crews to neutrals as part of their safety protocols. POCO fuses are incorporated into spring loaded cutout switches that physically blow open when the fuse is severed. Inside that thin white tube is a low-amp fusible link that blows and then causes the tube to flip downward, a physical indication that the fuse has blown.

 

[tom baker]

I am in SCE (Southern California Edison) territory ... they are upgrading all their systems 4160 primaries and replacing all their poles. And fusing all the primary branches at each transformer.
Also, the primary wires are now insulated.

This is because of wildfire prevention.

Our poco has done some insulating but they call it tree wire on the primary

 

[busman]

Our poco has done some insulating but they call it tree wire on the primary

It's typically called Hendrix Cable around here. Not technically insulated for the voltage, but good enough to withstand most tree contact. I guess technically, covered not insulated.

Mark

 

[Birken Vogt]

Hendrix cable is a different thing. They insulate the phases and bundle them closely and hang them from the neutral wire. "Tree wire" is insulated wires but still has the normal spacing.

Hendrix cable (aerial spacer cable)

Tree wire

 

[Elect117]

They use RED WHITE BLUE (A-B-C) for phase conductors and mark rotation accordingly.

Covered wire is becoming more common but it is not a substitute for tree trimming or clearances. The insulation will still degrade over time in the sun (as all things do) and it is expected to occur ~50 years from install date.

 

[mtnelect]

We are adjacent to Angeles National Forest and SCE is being "Pro Active"

1) Contracted tree service
2) Contracted Helicopters with imaging technology
3) Contracted Drones to double check imaging results

 

[busman]

Hendrix cable is a different thing. They insulate the phases and bundle them closely and hang them from the neutral wire. "Tree wire" is insulated wires but still has the normal spacing.

Hendrix cable (aerial spacer cable)

Tree wire

I believe you are correct, but around here, the slang is to call either Hendrix cable.

 

[mtnelect]

Also ... When SCE started with helicopters, I thought someone escaped from the Sheriffs station below us.

 

[mtnelect]

Southern California Edison - Pole Replacement

 

[LarryFine]

They use RED WHITE BLUE (A-B-C) for phase conductors . . .

They who? Don't assume it's the same everywhere. Red-yellow-blue is often used around here.

 

[Elect117]

They who? Don't assume it's the same everywhere. Red-yellow-blue is often used around here.

Socal Edison. It is in the title of the post.