De-energizing primary?

[mbrooke]

If a tree leans over and rests into 15kv tree wire is it necessary to de-energize the 12.47kv primary? This just happened next to my house. I still have power.

[steve66]

I find it had to believe those lines would still be powered. Seems like a tree would be enough to take out a re-closer.

[Tony S]

I’ve seen this happen 20+ years back on a 11kV OH line. The tree caught fire but the supply breaker didn’t trip. I had to phone the DNO (PoCo) to get the supply shut down.

I did get some benefit from it, two cows were killed and I got some good pieces of beef from the farmer.

[mbrooke]

I find it had to believe those lines would still be powered. Seems like a tree would be enough to take out a re-closer.

Ahem:

15kv tree wire

Which would be this


https://www.marmonutility.com/Portal...re_Systems.pdf

[mbrooke]

I’ve seen this happen 20+ years back on a 11kV OH line. The tree caught fire but the supply breaker didn’t trip. I had to phone the DNO (PoCo) to get the supply shut down.

I did get some benefit from it, two cows were killed and I got some good pieces of beef from the farmer.

Stray voltage is horrendous with 4 legs.

[Besoeker3]

Stray voltage is horrendous with 4 legs.

Yep. No insulating boots.........

[mbrooke]

Yep. No insulating boots.........

If only cows could fly as chickens do.

[Besoeker3]

If only cows could fly as chickens do.

Yep. I electrocuted my dog, not the current one (no pun intended), when I held on to an electric fence. He came up to me and nudged my hand. Dogs do. Wet grass, no boots for him. That was one helluva belt. He took off like a scalded cat but he was fine a day or so later.

[GoldDigger]

If a tree leans over and rests into 15kv tree wire is it necessary to de-energize the 12.47kv primary? This just happened next to my house. I still have power.

The insulation on the tree wire is apparently in good enough shape to withstand the applied voltage. But I would not under any circumstances try to clear the tree without first de-energizing the line. A mechanical break in the insulation or a broken wire as a result of a poorly planned attempt to prune or fell the tree could cause dangerous step and touch potentials over a wide region around the work site.

And, just in case the responsibility is not clear, any action in response to the leaning tree should be coordinated by POCO.

[steve66]

Ahem:



Which would be this


https://www.marmonutility.com/Portal...re_Systems.pdf

I missed the tree wire note. I didn't know that's what they call it.

[PaulMmn]

Yep. No insulating boots.........

See the movie Top Secret...

[mbrooke]

The insulation on the tree wire is apparently in good enough shape to withstand the applied voltage. But I would not under any circumstances try to clear the tree without first de-energizing the line. A mechanical break in the insulation or a broken wire as a result of a poorly planned attempt to prune or fell the tree could cause dangerous step and touch potentials over a wide region around the work site.

And, just in case the responsibility is not clear, any action in response to the leaning tree should be coordinated by POCO.

[mbrooke]

I missed the tree wire note. I didn't know that's what they call it.

They also have a single layer wire known as "covered wire" In theory it should not short out either is a tree touches it.

[mbrooke]

Update: They did cut the power for about 2 1/2 hours. Got it back 10 minutes ago. No damage to the pole or cross arm. Who ever invented tree wire deserves a Nobel prize.

[Hv&Lv]

We have tree wire on our 25kV circuits where the ROW is only 10 ft.
I have seen this stuff arching while it’s laying on the ground making glass.
ive also seen it energized for days with a pine laying over it and the wire pulled to within 10’ of the road.
it gets pretty at nights when the wet leaves on close trees are laying all over it, tiny little lights all over the wire...