Lesson 11

Question 1

The most common type of substation in use today is the air-insulated type.

True or False?

The Guidebook for Linemen and Cablemen 2nd Ed. Textbook, Chap. 4, Pg. 119, Paragraph 1, Sentence 1

Answer 1

True

Question 2

Common names given to bus types are main bus, ring bus, and ____ bus.

a. coil
b. core
c. displacement
d. transfer

The Guidebook for Linemen and Cablemen 2nd Ed. Textbook, Chap. 4, Pg. 121, “High Voltage and Medium Voltage Bus,” Paragraph 1, Sentence 4

Answer 2

d. transfer

Question 3

One of the common methods to make connections to aluminum tubular bus is with ____.

a. bolted connectors
b. hammer forged joining
c. threaded Tee fittings
d. Tungsten Inert Gas (TIG) welding

Substation Construction Guidelines Textbook, Chap. 6, Pg. 160, Paragraph 4, Sentence 1

Answer 3

d. Tungsten Inert Gas (TIG) welding

Question 4

Older substations with copper rigid bus systems use welded connections.

True or False?

Substation Construction Guidelines Textbook, Chap. 6, Pg. 157, “General,” Paragraph 2, Last Sentence

Answer 4

False

Question 5

Minor defects in rigid bus may be repaired by ____.

a. filing, then polishing with a fine emery cloth
b. installing a coupling
c. media blasting
d. using a disc grinder

Substation Construction Guidelines Textbook, Chap. 6, Pg. 157, “Rigid Buses,” Paragraph 3, Sentence 3

Answer 5

a. filing, then polishing with a fine emery cloth

Question 6

A ____ is a flexible bus consisting of a stranded conductor strung between substation structures and may be supported by suspension insulators

a. cable bus
b. high-line bus
c. strain bus-bar
d. tensioned wire bus

Reference: Bus/Jumpers—Types, “Introduction,” Paragraph 2, Sentence 1

Answer 6

c. strain bus-bar

Question 7

Insulated bus-bar is a rigid tubular aluminum conductor installed in a larger metal tube, filled with high pressure ____ gas.

a. argon
b. helium
c. nitrogen
d. sulfur hexafluoride

Reference: Bus/Jumpers—Types, “Introduction,” Paragraph 2, Last Sentence

Answer 7

d. sulfur hexafluoride

Question 8

The type of substation bus that is a rigid bar supported by insulators and covered by a grounded metal shield is the ____ bus-bar.

a. cylinder
b. insulated-phase
c. strain
d. tubular jacket

Reference: Bus/Jumpers—Types, “Introduction,” Paragraph 2, Sentence 2

Answer 8

b. insulated-phase

Question 9

The most common types of rigid bus-bar used in substations are flat, hollow tube aluminum, and ____.

a. angle
b. channel
c. rod
d. strain

Reference: Bus/Jumpers—Types, “Introduction,” Paragraph 3, Sentence 1

Answer 9

a. angle

Question 10

Where high-current substations are built, ____ bus-bars are used because its shape allows heat to dissipate more efficiently.

a. angle
b. flat
c. hollow tube
d. strain

Reference: Bus/Jumpers—Types, “Introduction,” Paragraph 3, Sentence 2

Answer 10

c. hollow tube

Question 11

Strain type bus-bars are used in substations primarily for ____ conductors.

a. high voltage transmission
b. main bus
c. ring bus
d. transfer bus

Reference: Bus/Jumpers—Types, “Introduction,” Paragraph 1, Sentence 2

Answer 11

a. high voltage transmission

Question 12

Hollow tube aluminum bus is the easiest type to connect to with bolt-on jumpers.

True or False?

Reference: Bus/Jumpers—Types, “Introduction,” Paragraph 4, Sentence 3

Answer 12

False

Question 13

Because of the lower voltages on the secondary side of a transformer, a ____ bus allows for closer spacing and is easier to connect with bolt-on jumpers.

a. copper rod
b. flat or angle aluminum
c. hollow tube
d. stranded wire

Reference: Bus/Jumpers—Types, “Introduction,” Paragraph 4, Sentence 2

Answer 13

b. flat or angle aluminum

Question 14

If the load is heavy enough, two or three large copper conductors may be used per phase as jumpers.

True or False?

Reference: Bus/Jumpers—Types, “Jumpers,” Paragraph 2, Sentence 3

Answer 14

True

Question 15

Expansion and contraction of rigid bus-bars due to load variation and ambient temperature changes are small amounts and are generally disregarded by designers.

True or False?

Reference: Bus/Jumpers—Types, “Jumpers,” Paragraph 1

Answer 15

False

Question 16

If multiple or parallel jumpers are used on the same phase, they must be ____.

a. bolted or wired together
b. copper conductors
c. rapped with tape to form a bundle
d. solid wire conductors

Reference: Bus/Jumpers—Types, “Jumpers,” Paragraph 2, Last Sentence

Answer 16

a. bolted or wired together

Question 17

Vibration of substation buses will occur if the spans are long enough to vibrate and the ____.

a. bus diameter is 3” or more
b. bus temperature is below 40°F
c. phase separation is close
d. wind blows across the bus at right angles

Reference: Bus/Jumpers—Types, “Vibration,” Paragraph 1, Sentence 2

Answer 17

d. wind blows across the bus at right angles

Question 18

Only round hollow aluminum substation buses will vibrate.

True or False?

Reference: Bus/Jumpers—Types, “Vibration,” Paragraph 1, Last Sentence

Answer 18

False

Question 19

A substation bus will vibrate because the supporting insulators are rigid and cannot absorb any vibrations.

True or False?

Reference: Bus/Jumpers—Types, “Vibration,” Paragraph 1, Last Sentence

Answer 19

False

Question 20

If a four-inch hollow tube bus is used, the support separation can be up to ____ before damping should be used.

a. 13’
b. 17’
c. 21’
d. 24’

Reference: Bus/Jumpers—Types, “Vibration,” Paragraph 2, Sentence 5

Answer 20

b. 17’