generator to a laundry 50 feet
will be in soil.
Using a 40-foot
away.
If the total demand load of
pole height, you specify that the
the laundry is 41 KVA, what size
poles are to be set into rock and
wire will you specify?
soil respectively what depths?
a. 2
c. 6
a. 4.0 and 5.5
c. 4.5 and 6.0
b. 4
d. 8
b. 4.0 and 6.0
d. 4.5 and 6.5
6. Why is weatherproof covering
11. You are designing poles to be
specified
for
secondary
set 150 feet apart for a prevailing
distribution in TO construction?
temperature of 60 F. For a primary
a. is safer
feeder line on your installation,
b. permits closer spacing of wires
what is the minimum distance above
c. simplifies splicing of wires
the ground that you can attach
d. increases the strength of wires
wires to the poles for an area that
involves crossing public streets
7. If in a given distribution
and driveways to resident garages?
system a 5 percent voltage drop
a. 18'7"
c. 28'3"
will occur in transmitting power to
b. 22'2"
d. 30'8"
the farthest load in the system,
how much voltage must be impressed
12. In problem 11, what would be
by the generators in order to have
the minimum height for attaching
208 volts available to the user?
wires to poles if the line had to
a. 219
c. 308
cross a railroad track?
b. 232
d. 327
a. 18'7"
c. 28'0"
b. 20'2"
d. 30'2"
8. If a 10 3W 120/240V system is
being used to supply a 6 KVA load
13. What is the minimum allowable
with a number 8 wire, what is the
stringing sag in feet at 60F for a
percent voltage drop in its 250
4/0 (0000) hard-drawn bare copper
foot length?
wire using wood poles and a 450
a. 2.0
c. 3.2
foot pole spacing? (Tension in the
b. 2.5
d. 4.0
wires must not exceed one-half the
wires' ultimate strength.)
Third requirement.
Multiple-choice
a. 4
c. 8
exercises 9 through 13 deal with pole
b. 6
d. 12
selection.
Fourth requirement.
Multiple-choice
9. If line poles are spaced at
exercises 14 through 18 will cover
250-foot intervals, what is the
wire
size
determinations
for
the
required vertical wire spacing in
system in the following situation:
inches?
a. 6
c. 12
Situation. As utilities officer of a
b. 9
d. 18
TO installation you have been directed
to furnish electric power to the
10. In repairing a damaged 12-mile
portion of the installation shown in
gap in a power line, you find that
figure 19.
The generator and feeder
some of the poles will be located
line locations have been determined as
in
rocky
terrain
while
some
shown in figure 20. The following data
will apply:
2-26
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