> Well, if we're going to start telling "fish stories" about arcs, I'll hav=
e to share
> mine...
>=20
> More years ago than I would like to count, I developed the software that =
ran
> the Niagara Falls Robert Moses hydroelectric plant. There were 13 units, =
each
> 167MW, in the main plant. The units generated at 13KV, but the voltage wa=
s
> immediately stepped up to 115KV by a transformer in a concrete enclosure
> with a large hole (for ventilation I suppose) in the concrete roof. A
> maintenance worker was up on top of the enclosure and dragged an
> extension cord across the roof, and it fell into the hole, directly onto =
the
> 115KV line. I don't know how long an arc was sustained, but I do know the
> unit was offline for month(s?) to repair the damage. The surge on the
> extension code took out (vaporized, really) the entire length of the
> extension code, and the wiring in the conduit leading to the outlet it wa=
s
> plugged into.
> Amazingly, the maintenance worker survived, I believe without any
> permanent damage.

One course I was on when an apprentice was also attended by a guy who worke=
d for New Zealand electricity Department (at the time the outfit responsibl=
e for the distribution network across the whole of NZ). He told us stories =
of being in the back country, and the 'standard' way of testing the umpteen=
 kV distribution lines was to send a pulse down them which was measured som=
ehow at the far end to test the integrity of the lines.

Standard pulse generator was a length of #8 fencing wire somehow flung over=
 the grid wires (I don't recall him elaborating on how they did it) which w=
ould cause a short, an almighty flash of light that would light up a valley=
 even in full daylight, and create the required pulse down the grid.

Changed to OT as we are going way off topic now ...

--=20
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