[LINK] An Overhead NBN

[Paul Brooks]

On 08/11/2013 09:55, Karl Auer wrote:
> On Fri, 2013-11-08 at 09:25 +1100, Jan Whitaker wrote:
>> Common sense tells me that putting non-destructable es can l(low?
>> destructable) components along poles wouldn't be any different than
>> putting them underground EXCEPT for the danger of being crashed into
>> and broken by some other thing, like a car.
> Poles take lightning strikes. Poles fall over and cause damage when they
> do.

Cables strung along poles are eaten by cockatoos, and knocked out by vehicles. Cables 
pulled underground are eaten by rats, and knocked out by ditch-diggers and concrete 
saws. Its a toss-up.
Wooden poles burn down in bushfires. Sufficiently deep underground cables rarely melt 
- but can be washed away in floods.

Overhead cabling is faster and cheaper to install, but more unsightly - but the 
organisation putting them up doesn't have to pay for unsightly. At least optical fibre 
cable, without any metallic strength component, can be strung up along the power wires 
rather than a metre below them reducing the visual impact as they look like just 
another power wire - they *should* at least look better than HFC cabling.

P.






>   Poles are unsightly. Poles (as you say) are additional things to be
> run into. Poles can be easily climbed by the young and the insane. Poles
> are obvious, they can be found easily for purposes of attack (whereas
> trenches disappear quite quickly; pits are not obvious; pits can be
> locked). Poles, insulators, mounts and the cables themselves can be shot
> at (very common in rural areas). Suspended cables can be easily reached
> with thrown objects esp. shoes. Suspended cables can be hit by other
> things - high trucks, extended ladders, birds, aircraft, kites etc. When
> a pole fails, for any reason, the cables pose a great danger, especially
> if electrified. Failure in a trench or pit is generally harmless. Poles
> are vulnerable to extreme weather, especially wind and (in some
> countries) ice. Poles block some land uses - can't run or drive through
> them, can't build over them, can't build too near to them etc etc. You
> can't plant trees near the poles or near the path of the wires.
>
> Underground has some similar disadvantages, but in general far fewer, in
> particular it's not unsightly and they are invulnerable to just about
> everything except an earthquake (and maybe flood).
>
> Regards, K.
>