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Utility poles

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Re: Utility poles

#161

Post by mikro2nd »

throwaway7645 wrote: post #91
ggm wrote: post #55

Earlier quoted context omitted.

Stobie poles are used a lot in Italy and southern Europe. They all seem to be from the 1920s and have really bad "concrete cancer" and the underlying steel is rusting out. Quite picturesque in a "oh crap, there is 220v on top of this rusting pile..." kind of way. "the prime of miss jean brodie" is set in pre-WWII scotland and an opening credit scene walks past two concrete lamp posts. My mother (who was an architectu…

220V isn't very high in the power world. The US has 765 KV. I'm not sure what the highest voltage cable in the world is, but now I'm curious.

There is a transmission system in India rated for something over a million volts. The last time I looked it was only carrying about 800kV, though. Just why this was so was not explained. IIRC it was on the Wikipedia article on transmission grids.

Re: Utility poles

#162

Post by fredley »

Waterluvian wrote: post #2

I absolutely love reading about a topic from a super enthusiastic non-expert. I want to subscribe to a weekly series called "Reasonably Intelligent Person Obsesses Over Something"

Further to that, I love that he doesn't provide answers to all of the things he's wondering about.

Re: Utility poles

#163

Post by PhantomGremlin »

rothrock wrote: post #155

https://en.wikipedia.org/wiki/Transformer_oil c'mon really? you didn't even look? What is this? You're "interested in utility infrastructure" !? 7000 Volt lightning? most household uses ... they want single-phase power!? In 1910, maybe.

most household uses ... they want single-phase power!? In 1910, maybe.

Huh? In the USA all residential is single-phase. Although there's a center tapped transformer involved, which is what gets you both 120 V and 240 V from one phase. This arrangement is called "split-phase": https://en.wikipedia.org/wiki/Split-phase_electric_power#Nor...

Name one "household use" in the USA (which is where the author lives) that doesn't use single-phase power? I'll give you a head start, I once lived in an apartment building that used 120V/208V for electric hot water heaters. But offhand I can't think of anything else.

Re: Utility poles

#164

Post by aaron695 »

adonovan wrote: post #47

Those cans are filled with transformer oil, which until relatively recently consisted mostly of polychlorinated biphenyls or PCBs. Imagine how many of those cans exist across the United States and you get a sense of how big the PCB industry used to be, and why rivers such as the Hudson in New York [1] and the Housatonic in Massachusetts [2] are polluted with olympic swimming-pool sized quantities of the durable oily…

> In recent years, thieves in Kenya (which has yet to replace PCBs with something less toxic) have been vandalizing [3] transformers and selling the oil to street vendors

I see no confirmation on this. Sounds like an urban legend. All reports come from the one source which also talks about the legitimate reason of scrap stealing.

The doctors quote should be the biggest tip off.

If it makes people sick(Off what seems like a once off) why would street vendors use it? This is just nonsense.

Why do we demonize people from the underdeveloped world. Whats the point of cheap oil if your customers never come back. It lacks basic commercial sense. How can this become widespread.

Nonsensical urban legends on the other hand I'd guess they catch like us.

Another Urban Legend - transformers contain P2P, which tweakers drain them for. It's interesting lore at least, they are a big part of the community.

Re: Utility poles

#165

Post by toomanybeersies »

gunzel wrote: post #149
toomanybeersies wrote: post #142

Earlier quoted context omitted.

Is that an American thing? I've never seen 4 lines on a power line in New Zealand unless they're also carrying telephone lines.

I think New Zealand is the same as Australia with 5 wires: the 3 phases, neutral (the central return wire) and earth. Grabbing a random location in Auckland off Street View shows 5 wires: https://goo.gl/maps/wz1W73uWAiz

Depends on where you are in the country. Here's some 3 wire I found by dropping a random pin: https://goo.gl/maps/MkoiprJ1gWM2

I've always remembered it being 3 pin around where I grew up.

Re: Utility poles

#166

Post by kbart »

_Codemonkeyism wrote: post #158

As a German I'm always amazed by the ugliness of those power and telephone poles in other countries. There is talk here to also build phone lines with poles in the future as it is cheaper, hope this never happens.

Phone lines? Are line phones still so popular in Germany that it even requires network expansion? In my country copper lines are basically left to rot as line phones are being replaced by cell/IP phones rapidly. In some cases people living in remote areas were issued free cell phones, because it was cheaper than repairing old copper lines.

Re: Utility poles

#167

Post by squeed »

nkurz wrote: post #157
agwa wrote: post #86

Earlier quoted context omitted.

Thanks for the recommendation; that book looks amazing! And there's a revised 2014 edition in print: http://industrial-landscape.com/#/buy

Thanks to both of you. It does seem to be a great book! I've requested it (well, the older version) from my library. Apropos this article: http://industrial-landscape.com/#/18

Enjoy it! I've had this book for years. It's one of my treasured possessions.

Re: Utility poles

#168

Post by vilda »

Transformer oil is there primary for cooling and secondary for corrosion resistance. When you see transformer burning, it's the oil inside. Larger transformers cycle oil through pipes visible outside.

In the Czech Republic (or at least in some parts) pole numbers and their positions are shared with emergency services. If you are disoriented, reading the number identifies your exact position. Works for railway crossings as well.

Update: typos

Re: Utility poles

#169

Post by bmn__ »

mjd wrote: post #117
Waterluvian wrote: post #2

I absolutely love reading about a topic from a super enthusiastic non-expert. I want to subscribe to a weekly series called "Reasonably Intelligent Person Obsesses Over Something"

Thanks! Can I suggest that you might enjoy following my blog regularly? In addition to utility poles, I have also discussed this year: Samuel Johnson's feud with James Macpherson, a fraudulent poet; the panicked history of England in 1533 after Henry VIII's mistress got pregnant; the Slaughter electric needle injector; how plutonium is used to power medical devices; equivalents of "Joe Blow" in Turkish and Hebrew. Al…

Why do you denigrate your own work so often, though? Most of the time, when someone posts your articles, you reply "does this guy ever shut up" or "this post sucks".

Re: Utility poles

#170

Post by M_Bakhtiari »

PhantomGremlin wrote: post #163
rothrock wrote: post #155

https://en.wikipedia.org/wiki/Transformer_oil c'mon really? you didn't even look? What is this? You're "interested in utility infrastructure" !? 7000 Volt lightning? most household uses ... they want single-phase power!? In 1910, maybe.

most household uses ... they want single-phase power!? In 1910, maybe. Huh? In the USA all residential is single-phase. Although there's a center tapped transformer involved, which is what gets you both 120 V and 240 V from one phase. This arrangement is called "split-phase": https://en.wikipedia.org/wiki/Split-phase_electric_power#Nor... Name one "household use" in the USA (which is where the author lives) that does…

It is strange though, that residential three phase is so uncommon there, especially when the single phase voltage is only 110, further sacrificing efficiency for high power applications.
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