The Wallace miner. [volume] (Wallace, Idaho) 1907-current, 1920-09-23

~ mn the smart has been considered bl
Il many mine operators for a number o
3. years. There are several methods il
use in different mining districts ant
d, so far as the writer is aware the,
= have been further developed in Utah
} than in any other state. The --latest
! installations are of interest because
they use a very low voltage circuit
for the shaft wires and also because
e the wiring can be so arranged that
the hoist can be stopped from the
cage if SO desired.
The first installation in Utah was in
the shaft of the Centennial Eureka
mine under the management of c. +.
Allen 1t was placed in operation in
the summer of 1899, and has been in
continuous and satisfactory operation
for 81 years. The arrangement con-
sists of two bare wires down the
shaft carrying a current at 60 volts
potential with a device on the cage
for making connection between the
two wires. This device is simply
short piece of wire which is thor
oughly insulated from the cage and is
operated by short lever Whenever
the cage rider wishes to signal the
engineer he pulls down the lever fore
ing the short wire out against the two
bare wires. thus making a circuit
which rings the bell in the hoist room
\ similar device was placed in the
Grand Central shaft at Mammoth,
/ Utah. but was later abandoned The
cause of failure was reported to be
that the shaft was very wet
How System Works at Eagle & Blue
Bell.
At later date system having the
same general arrangement as that
used in the Centennial Eureka mine
was placed in the shaft of the Eagle |
and Blue Bell mine at Eureka Utah |
but dry batteries were substituted |
reducing the voltage to about 10 volts |
This shaft is wet in places, but no /
trouble has been experienced The |
Eagle and Blue Bell mine is under the |
management of liner PETIT of Salt
Lake City, and several improvements
on the method have been made by the
mine electrician. James Strang in
consultation with Leonard Wilson, of
Salt Lake
In order to give a better idea of the
possibilities and application of the
system, it should be stated that the
hoist is a double-reel modern electric
hoist with oil operated clutches and
brakes. The clutch and brake for
each reel are actuated by different
movements of the same control lever
The hoist has the usual safety devices
such as limit switches In the head
frame, position switches for each reel
and ball governor control. These {
safety devices are operated by what
may be termed the control wiring, L
which is in series with a no-voltage
release on the switchboard Should {
the circuit in the control wires be
broken, the no voltage release acts. 6
which cuts off the power and auto
applies the brakes For ex- {
ample, if the cage should be pulled
up to the limit switches, the circuit c
would be broken, automatically stop
ping the hoist. Ia
This arrangement of wiring for the
safety decises is not materially differ C
ent from that used ON other electric y
noists, and is mentioned here solely to
show that opening the control circuit Il
$ all that is needed to stop the hoist p
In the Eagle & Blue Bell shaft there o
ire two No. bare copper wires, one Il
IN each side of the shaft guides One Il
If these wires is used for signalling
rom the levels, the second wire form
mo- 10
lso used to make the circuit for ring H
ng the bell from a moving cage.
Signalling From the Cage.
AS regards signalling from the cage II
may be assumed that there is only re
ne bare wire in shaft, this wire ex- III
ending into the hoist room and Ia
Trough an ordinary Western Union f'
clay switch to the ground On the y'
age is a battery of six dry cells in dc
osed in a piece of iron pipe for pro- IT,
sction. One terminal of the battery M
connected to the hosting cable and al
thus grounded through the hoist Dl
he other terminal is connected with DO
n ordinary push button switch and Ia
piece of curved copper plate which, 81
ihFruH VI q SAldlA ltFtIs can Dt
ished out against the bare wire. The of
lsh button is on the same level ca
hen the cage rider pulls the lever, civ
the same time pressing the button, la
Trent flows from the dry cells isl
rough the bare wire, through the m;
lay into the ground, thence through DO
e hoist cable back to the cells The tir
rrent flowing through the relay ap
oses a separate electrical circuit tn
hich rings the signal bell The cur is
Mt for the bell circuit is supplied de-
r 30 dry cells in the hoist room, but de-
injection could be made with a di-
ct power or lighting circuit. bel
The important feature of this ar ret
ngement is that the dry cells, plac- the
on the cage, give a low voltage civ
trent, only 10 or II volts, eliminat- DEF
p all possibility of danger, such as the