121–130 of 213 posts
I'm now spotting fiber optic cables on different poles :) They commonly use distinguishable splice enclosures which look like this: * https://fiber-optic-catalog.ofsoptics.com/Asset/Closure.jpg * https://thumbs.dreamstime.com/z/fiber-optic-enclosure-splice...
Your bottom picture also shows half of a snowshoe fiber slack storage location. They are used at almost every splice so the splice can be moved to the ground easily and placed into a splicing trailer. That fiber pictured is a strand and lash construction where a high strength steel wire is placed and then the fiber is basically tied to it. We have stopped using any of it in favor of ADSS fiber which means all dielect…
Interesting, thanks for pointing out how it's called and what's the purpose of it. I saw it around, but had no idea what it's for :)
I noticed though, that for example Optimum fiber network is using it, while Verizon one does not.
Regarding three-phase power: The electrical outlets in your home have two power-carrying prongs. The third prong is just for safety (it connects to the ground), and should never carry power unless something is going horribly wrong. In that case, the power should hopefully prefer to reach the ground through that third wire than through your human body. Anyhow, the voltage in those two power-carrying wires is constantl…
“Isn’t quite how it works” is a gross understatement. I apologize, but while there’s some correct facts, the entire narrative you spun clearly shows you don’t have the first clue what you are talking about. I really want to be as polite as possible, but what did you expect to accomplish by posting this?
Regarding three-phase power: The electrical outlets in your home have two power-carrying prongs. The third prong is just for safety (it connects to the ground), and should never carry power unless something is going horribly wrong. In that case, the power should hopefully prefer to reach the ground through that third wire than through your human body. Anyhow, the voltage in those two power-carrying wires is constantl…
In some places though, (I know it's common in New York, and also in a lot of datacenters), they do something like you describe, and hook 2 phases of a 3 phase system together. Since these are only 120 deg out of phase from each other instead of 180 in the split-phase system, you get less voltage, specifically 208V.
Earlier quoted context omitted.
Do the distribution transformers have "winter" ratings like the local center tapped step down transformers that feed houses? Around here it is pretty clear that Georgia Power doesn't pay much attention to the name plate ratings, winter or otherwise, when sizing and determining the number of homes per xformer.
Distribution transformers are not usually thought of as having a winter rating. On the other hand, distributions lines definitely do. Sometimes work on lines can only be done during the winter, because the load has to be shifted to lines that can only handle the increased temporary load during the winter. There is a science and an art to sizing residential xfmrs. Generally is depends on the square footage, number of…
But I never thought about pole xformer sizing until this house. Our 35kVA (summer) faceplate xformer services nine homes. Even though it browns, it keeps on working. They've got a lot of margin, it seems
In Australia we have a life extension program for hardwood poles which slides a steel formed sock/support down the side to stabilise it for many a year more after a hard life. We had some issues with corrosive dog wee. Tar treatment sometimes works. Also steel collars to keep possums off the top structure. In Europe there are other platforms above the transform and wire complex for bird nests. Storks, cranes all abov…
As I understand it one of the largest concerns in AU are the wildfires damaging circuits connecting the disparate grids. There was some conversation about replacing some of the network poles with fire resistant poles in order to try and avoid the high number of outages caused by fires during the dry season. I'd be interested to know how that project went, and if it was successful.
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…
Earlier quoted context omitted.
While the second half of your comment is correct: >> The electrical outlets in your home have two power-carrying prongs. >Only one of the prongs carries power. The other is attached to the earth, and is always at zero volts. Voltages are about potential differentials, so "zero volts" is relatively meaningless without context. The neutral line is required by the electric code to be connected to earth at the electric p…
> Both prongs absolutely carry power. Both carry current . But not power. Power is volts * amps, and the neutral is defined as zero volts (if you ignore the voltage drop). > you can get shocked when working on junction boxes for the neutral line Only from the voltage drop on that wire. It's not the full 120v. (Unless it's cut of course, but that's a whole different story.) > Here you use voltages as a relative measur…
"Electric power in watts produced by an electric current I consisting of a charge of Q coulombs every t seconds passing through an electric potential (voltage) difference of V is
P = work done per unit time = VQ/t = VI
Note that V is the "electric potential difference" and it take two conductors to supply power.
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…
Yes, PCBs have high thermal conductivity and low electrical conductivity. Also better thermal stability than hydrocarbons. But unfortunately, quite toxic as well. And they tend to be contaminated with dioxins, which are far more toxic. Seriously, PCB/dioxin contaminated oil sold for frying? That is insane. But then, people sometimes adulterate sugar with lead acetate :(
Everything from copper to make pickles green, to molten lead to clarify wine.