Power Line to my house was broken

[ponytug]

A coil of wire has two ends. A coil in a transformer has two ends in the primary. You can wire the transformer so that one end of the primary coil goes to ground and the other is at a high voltage relative to ground. That saves the power company 50% running one wire instead of two. But you need to have really good grounds, and your soil better not dry out. I am not saying I think that it is good practice, just trying to add to MossRoad's great explanation. It does provide lots of places to dump the surges from lightning strikes.

Yes, they probably have the center tap of the low voltage tied to the low potential end of the high voltage coil and both of those tied to ground. That would also leverage all the grounds at the homes on the transformer as additional sinks.

Part of the power for Southern California comes from the Washington/Oregon border in a DC high voltage line. They ran a wire for the positive and grounded the negative in the ocean, so the negative return flows through the ocean. Presto! Only one wire needed. Old fashioned coils on engines did a similar thing; one low voltage positive in, one high voltage positive out, and both of the other halves of the circuit running through the frame.

Back to Eddie's issue. The power company appears to have run a ground/neutral/low potential line for its high voltage circuit as well as a high potential wire. (The high voltage circuit having one line at ground potential and one line at high voltage(e.g.7800V?).) That the power is still working at Eddie's suggests that they grounded this low potential line in a few places and those grounds are providing the other half of the high voltage circuit, despite the broken wire. MossRoad had a nice illustration above.

The loose wire could be at ground potential, or close to it, or not, and people have died from potentials as small as 46V. I wouldn't get near those wires, as it would be putting a lot of faith in the remaining grounds being able to absorb however much power gets used in the area. As the resistance in the remaining grounds go up, the potential will rise.

More mud?

All the best, Peter

 

[Industrial Toys]

How many volts was that DC line? Where did they get the DC? Is that to accomodate some sort of storage medium?

I mean, yeah, telegraph I believe used EARTH ground all the time.

If you plugged your lawn mower into the hot lead and ran the neutral to a ground rod you drove into the lawn, it would probably at best hum, depending on ground resistance and distance to the nearest grounding point. Mind you that's just 120Volt.

 

[MossRoad]

It's dark now. Wear a headlamp and get up there with your ALCAN Ladder. lol Don't forget to take your HF meter.

Thanks for the tips. I'm sure the neighbors won't be concerned.

 

[MossRoad]

My head hurts. Goodnight folks.

 

[ponytug]

How many volts was that DC line? Where did they get the DC? Is that to accomodate some sort of storage medium?

I mean, yeah, telegraph I believe used EARTH ground all the time.

If you plugged your lawn mower into the hot lead and ran the neutral to a ground rod you drove into the lawn, it would probably at best hum, depending on ground resistance and distance to the nearest grounding point. Mind you that's just 120Volt.

It is called the Pacific intertie and it runs at 500,000 volts, and carries over 3MW.
Pacific_DC_Intertie (Path 65)
There is another DC line from LA to Utah. (Path 27)

Using DC saves energy, (Basically, DC runs current through the whole wire. AC runs current more on the surface, so less DC resistance for the same size wire.), but you need to be moving a lot of power a long way for it to pencil out, as it does cost to have the equipment to rectify the AC into DC and back to AC again. Somewhere over a couple of hundred miles is the usual break even point, though with improving electronic controls that number has dropped to tens of miles in some cases.

There is no storage today. They get DC from AC the same way your alternator turns AC into DC that uses diodes, except the high power versions are called thyristors and function slightly differently. (Lots of new variants now, but that's just getting into the weeds.) Going the DC to AC uses specialty semiconductors to make smooth AC. "Pure sine wave" AC.

Using DC also lets you connect separate parts of the electrical grid together, because you go AC grid #1 to DC to AC grid #2, so your two AC grids can both be at 60Hz, but not necessarily synchronized to each other. Japan runs on both 50Hz and 60Hz, and uses DC to tie them together a little bit.

The recent Texas power issues were exacerbated by a lack of AC/DC/AC interties and and intertie capacity.

And now back to Eddie's downed wires...

All the best,

Peter

 

[ohiogar]

Next door to me is a natural gas line with a tap that the gas company is currently working on. They are in the process of running a new gas line down the road and in the evening, they park the excavator inside the fenced area around the tap.

Yesterday I went out front to mow the weeds along the road and at the entrance to my place. While mowing, I noticed a cable hanging on my fence. It was so out of place that I just mowed around it while processing what it was. It took me a good ten seconds to comprehend that it was the bottom power line to my house. It was broke pretty clean, and just guessing, it happened exactly over the gate into the fenced area of the gas line tap.

I called 911 and the fire department was there in ten minutes. The Chief said it was the neutral line and that it wasn't hot. I could keep mowing and the power company would be out later to fix it.

Since I still have power at my house, I guess it's not that big of a deal. But what I don't understand is how do I still have power at my house? Top wire is hot, bottom wire in neutral. But if you don't need the bottom wire, why have it?

Hello from Ohio,
About 20 years ago we had an ice storm and the electric was out for more than a week. I ave a wood stove and generator so no big thing.
The power came back on and everything seemed to work but the microwave would not get hot.
There ere Power company crews everywhere so I started complaining that something wasn't right.
One guy from Virginia power company put a meter on my line and said I was nuts the power was fine.
I tried to get them to put a load test on my line and they just walked off.
It turns out much later that:
I had 2 plastic coated lines coming from the pole AND a bare aluminum line that I just always assumed was just to support the other two wires. These lines coursed through the crotch of a huge cherry tree.
Well right in the crotch of the cherry tree the bare aluminum wire had broken in two and that was the ground for our house. We had voltage but no amperage.
That could have been really dangerous .. deadly!!
Just thought I would throw this out there.
regards

 

[MossRoad]

Hello from Ohio,
About 20 years ago we had an ice storm and the electric was out for more than a week. I ave a wood stove and generator so no big thing.
The power came back on and everything seemed to work but the microwave would not get hot.
There ere Power company crews everywhere so I started complaining that something wasn't right.
One guy from Virginia power company put a meter on my line and said I was nuts the power was fine.
I tried to get them to put a load test on my line and they just walked off.
It turns out much later that:
I had 2 plastic coated lines coming from the pole AND a bare aluminum line that I just always assumed was just to support the other two wires. These lines coursed through the crotch of a huge cherry tree.
Well right in the crotch of the cherry tree the bare aluminum wire had broken in two and that was the ground for our house. We had voltage but no amperage.
That could have been really dangerous .. deadly!!
Just thought I would throw this out there.
regards

I think that was the neutral for your house. It's tied to ground in your service entrance box.

 

[ponytug]

Hello from Ohio,
About 20 years ago we had an ice storm and the electric was out for more than a week. I ave a wood stove and generator so no big thing.
The power came back on and everything seemed to work but the microwave would not get hot.
There ere Power company crews everywhere so I started complaining that something wasn't right.
One guy from Virginia power company put a meter on my line and said I was nuts the power was fine.
I tried to get them to put a load test on my line and they just walked off.
It turns out much later that:
I had 2 plastic coated lines coming from the pole AND a bare aluminum line that I just always assumed was just to support the other two wires. These lines coursed through the crotch of a huge cherry tree.
Well right in the crotch of the cherry tree the bare aluminum wire had broken in two and that was the ground for our house. We had voltage but no amperage.
That could have been really dangerous .. deadly!!
Just thought I would throw this out there.
regards

Which illustrates why you don't want to rely on a ground or two to absorb the return current...

All the best,

Peter

 

[kenmbz]

How many volts was that DC line? Where did they get the DC? Is that to accomodate some sort of storage medium?

I mean, yeah, telegraph I believe used EARTH ground all the time.

If you plugged your lawn mower into the hot lead and ran the neutral to a ground rod you drove into the lawn, it would probably at best hum, depending on ground resistance and distance to the nearest grounding point. Mind you that's just 120Volt.

There is no noticeable DC in an AC distribution. Lawn mower to hot lead would vaporize quite well.

My comment is to stay away from downed wires. There is always a chance it could be unbalanced at some point.

 

[Diggin It]

There is always a chance it could be unbalanced at some point.

Hey, I resemble that remark!!!