The Wallace miner. [volume] (Wallace, Idaho) 1907-current, 1918-06-13

''ai appdidtus Is installed TO produce
1t at the point of use, as direct eur.
rent cannot be transmitted economi.
cally but a short DISTANCE on account
. of the low voltage.
The power produced by the Mon
tana Power company is known as &C
cycle, three-phase alternating current
: BY 60 cycle is meant that the current
flows first in one direction, then the
other, 6o times each second. The
three phase part is not so simple. II
means that there are three alternating
currents so related and bound togeth
er That there are three alterations
for every cycle instead of one. This
means in q 6O-cycle system a differ
ence of 1-1S0 part of second be
tween cycles in the different phases
This may seem rather fast to you, but
1t is the reason why our generators
and your motors run at high speeds
Also when you know that electricity
travels $4,000 miles second you
will realize that We have to go some to
catch it,
Three Phase Circuit.
A three phase circuit requires three
wires; a two-phase circuit usually re-
quires four wires, hence costs more to
install and is not so efficient or fleX-
ible as the three phase system. For
these reasons many two-phase sys-
TENS have been changed to three
phase, except where they have grown
to such size. as in Seattle, that the
change could not be made, before the
greater advantages of the three phase
system were realized. In order that
| Great Fails may not be SO handicap
ped we will carry out this summer
plans made some years ago to change
from two phase to three phase and
will at the same time standardize our
distributing voltage and circuits.
There are II power plants supply
ing the Montana Power company's
transmission system extending from
Havre to Philipsburg, and Billings,
Montana, to Burke, Idaho. The two
largest plants are Volta and Rainbow
in Great Falls, supplying more than
half the total power The Thompson
Falls plant is next in size, then come
in order of capacity Hauser lake, the
Madison plant, Canyon Ferry, Black
Eagle and several smaller ones at the
Big Hole, Livingston, Billings and
Lewiston The Flint creek plant of
the A. c. M. company at Georgetown
is also connected. These are all water
power plants. The Hotter plant, now
being put in service. ranges between
the Rainbow and Volta plants in ca
pacity and is now required, for in the
near future we will use in Great Falls
| ing generated here.
Veritabe Network
The plants and all sub stations are
linterconnected in many places by a
| lines and provided with automatic
switching devices so that failure OF
any one line will cause it to be discon
nected automatically within two sec
onds and permit service to continue
over other lines without interruption.
At such times the lights wink little,
and If the automatic devices fail, as
they do occasionally, the lights go out
| for a minute or so.
The transmission lines are cared for
| by patrolmen who make inspections
periodically as required. They are sta =
toned from 20 to 40 miles apart, de-
pending on the nature of the country.
Fifteen out of a total of 80 patrol
men report to our Rainbow plant for
instructions four times each day over
private telephone lines which parallel
all high voltage transmission lines.
| In out of the way places we provide
building for the patrolman and his
family Married men are preferred, so
that there is some one at the patrol
stations at all times. In the rough
mountain country where the snow Is
heavy and it is necessary for the pa
trolmen to travel on skis in the winter
instead of horseback, emergency
cabins are provided, with supplies. At
advantageous places along the lines
are placed tool houses, where ropes
and blocks, insulators, tools and wire
are left for making repairs. At the
patrol stations and some other points
are located sectionalizing switches in
the power lines, which enable us to
locate trouble quickly: also to cut out
any section from 10 to 80 miles long
which may become defective, and use
the rest of the line.
Three Main Ones.
| We have three main transmission
voltages, 100000 volts. $1,000 volts and
SO, 900 volts. Out of total of 765
miles of 100,000-volt line. Go miles
are supervised from Great Falls. These
extend to Anaconda, Butte, Josephine
and Harlowton. There are also about
400 miles of similar line owned and
operated by the Milwaukee railway in
the electrified section, which is cleo
trically part Of our system.
The 100,000-volt line to Anaconda
passes through Hotter and Marys-
lvllle, thence to Anaconda. The double
tower line to Butte passes through