[R-390] OT - Transmission lines - local

[rbethman]

This changeover began a couple of decades ago.  It used to be that 
"local" lines carried 4160/2400 in a "Y" configuration.  Delta was 
provided for commercial locations that had 3 phase requirements as needed.

Then there began a "feeder" by "feeder" transition to 12470/7200.

The conductors were NOT changed, but by tying a second insulator in 
series with the original single, they would change out the pole top 
transformer.  As they did this, they began the path to the increased 
voltage supplied to residential customers.

One thing I was involved in while still in Uncle Sam's employ, was to 
perform annual Infrared scanning of these systems.  Uncle got "smart" 
and figured out it was a whole LOT cheaper to locate problem areas by 
locating the connections that were WELL over the "normal" temperature of 
the "system".  It has saved a LARGE amount of $$$ to have these problem 
spots noted, and let them schedule the required maintenance in lieu of 
the damaged/destroyed equipment, outages, and over-time paid to their crews.

Finally, my "local" municipality has acquired such equipment.  They have 
been contracting it out.  I've offered to go along with them when they 
begin on their own, but haven't heard back.

Oh well, their loss!

Bob - N0DGN