353 Final Exam Questions with Verified Correct
Answers
There are ? steps that are common to the installation of all substation equipment.
a.5
b.6
c.7
d.10
C.7
The minimum separation between bare live conductors in a substation (phase-to-phase) for
69 kilovolts is ? .
a.18"
b.21"
c.31"
d.53"
C. 31"
The minimum clearance for 115 kilovolts from a live conductor to the substation lattice
structure is ? .
a.42"
b.50"
c.58"
d.71"
A. 42"
Sulfur hexafluoride (SF6) gas is a common arc quenching medium used in new substation ? .
a.capacitors
b.circuit breakers
c.tap changers
d.voltage regulators
B. Circuit breakers
SF6 gas ? and will displace the air at the bottom of a confined space.
a.has the same properties as air and under pressure
, b.has the same viscosity as transformer oil
c.is heavier than air
d.is lighter than air
C. Is heavier than air
This photo is a close-up view of ? as might be used on a 220-kilovolt line.
a.capacitors
b.circuit breakers
c.tap changers
d.voltage regulators
B. Circuit breakers
Substation breakers are often defined by their ? and their type of operating mechanism.
a.current breaking capacity
b.insulating medium
c.physical size
d.voltage
B. Insulating medium
Substation circuit breakers can be operated by ? or ? controls.
a.AC / DC
b.DC / static
c.electronic / differential
d.mechanical / frequency
A. AC / DC
In new substations of 500 kilovolts, individual single-phase transformers are used because 3-
phase transformers at these voltages are extremely large and expensive.
Select one:
True
False
True
Disconnects in a substation cannot be used as grounding devices.
Select one:
True
False
Answers
There are ? steps that are common to the installation of all substation equipment.
a.5
b.6
c.7
d.10
C.7
The minimum separation between bare live conductors in a substation (phase-to-phase) for
69 kilovolts is ? .
a.18"
b.21"
c.31"
d.53"
C. 31"
The minimum clearance for 115 kilovolts from a live conductor to the substation lattice
structure is ? .
a.42"
b.50"
c.58"
d.71"
A. 42"
Sulfur hexafluoride (SF6) gas is a common arc quenching medium used in new substation ? .
a.capacitors
b.circuit breakers
c.tap changers
d.voltage regulators
B. Circuit breakers
SF6 gas ? and will displace the air at the bottom of a confined space.
a.has the same properties as air and under pressure
, b.has the same viscosity as transformer oil
c.is heavier than air
d.is lighter than air
C. Is heavier than air
This photo is a close-up view of ? as might be used on a 220-kilovolt line.
a.capacitors
b.circuit breakers
c.tap changers
d.voltage regulators
B. Circuit breakers
Substation breakers are often defined by their ? and their type of operating mechanism.
a.current breaking capacity
b.insulating medium
c.physical size
d.voltage
B. Insulating medium
Substation circuit breakers can be operated by ? or ? controls.
a.AC / DC
b.DC / static
c.electronic / differential
d.mechanical / frequency
A. AC / DC
In new substations of 500 kilovolts, individual single-phase transformers are used because 3-
phase transformers at these voltages are extremely large and expensive.
Select one:
True
False
True
Disconnects in a substation cannot be used as grounding devices.
Select one:
True
False
