godshawk wrote:Good luck with that, a power outage is an effective way to cut short almost all modern day human activity, even here in Uruguay
<<In 1844, the United States Congress granted Samuel Morse $30,000 to build a 40-mile telegraph line between Baltimore, Maryland and Washington, D.C.. Morse began by having a lead-sheathed cable made. After laying seven miles underground, he tested it. He found so many faults with this system that he dug up his cable, stripped off its sheath, bought poles and strung his wires overhead. On February 7, 1844, Morse inserted the following advertisement in the Washington newspaper: "Sealed proposals will be received by the undersigned for furnishing 700 straight and sound chestnut posts with the bark on and of the following dimensions to wit: 'Each post must not be less than eight inches in diameter at the butt and tapering to five or six inches at the top. Six hundred and eighty of said posts to be 24 feet in length, and 20 of them 30 feet in length.' One of the early Bell System lines was the Washington DC-Norfolk line which was for the most part, square sawn tapered poles of yellow pine probably treated to refusal with creosote. Some of these were still in service after 80 years.
In the United States electricity is predominately carried on unshielded aluminum conductors wound around a solid steel core and affixed to rated insulators made from glass, ceramic, or poly. Telephone, CATV and Fiber Optic cables are generally attached directly to the pole without insulators.
In the United Kingdom, much of the rural electricity distribution system is carried on wood poles. These normally carry electricity at 11 or 33 kV (three phases) from 132 kV substations supplied from pylons to distribution substations or pole-mounted transformers. The conductors on these are bare metal connected to the posts by insulators. Wood poles can also be used for low voltage distribution to customers.
In many places, as seen in the illustration, providers of electricity, television, telephone, street light, traffic signal and other services share poles, either in joint ownership or by renting space to each other.
On poles carrying both, the electric power distribution lines and associated equipment are mounted at the top of the pole above the communication cables, for safety. The vertical space on the pole reserved for this equipment is called the supply space. The wires themselves are usually uninsulated, and supported by insulators, commonly mounted on a horizontal crossarm. If non-insulated conductors touch due to wind or fallen trees, the resultant sparks can start bushfires. To reduce this problem, aerial bundled conductors are being introduced.>>
Psnarf wrote:Nor can we afford to purchase diesel generators for uninterrupted backup power.
neufer wrote:We can send men to the moon but we can't bury cables.
Psnarf wrote:> "We can send men to the moon but we can't bury cables."
Nor can we afford to purchase diesel generators for uninterrupted backup power.
[I don't know how many times while I was the national help desk in the early nineties some backhoe severed one of MCI's buried fiber cables. (All of our T1's were via MCI.]
This thread will self-destruct (or something) when APOD is back. Until then... yeah, I guess you can discuss the power outage or astronomical things here, if you want.
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