LADWP ELECTRIC STATION OPERATOR (CIRCUIT BREAKERS, DISCONNECTS, TRANSFORMERS) EXAM QUESTIONS WITH ALREADY PASSED ANSWERS!!

LADWP ELECTRIC STATION OPERATOR (CIRCUIT BREAKERS,
DISCONNECTS, TRANSFORMERS) EXAM QUESTIONS WITH ALREADY
PASSED ANSWERS!!

Question 1
One of the primary tasks of the Electric Station Operator is the __________ of high voltage
circuits.
A) construction
B) repair
C) switching
D) design
Correct Answer: C) switching
Rationale: Switching is the fundamental action an operator performs to control the flow of
electricity, isolate equipment, and reconfigure the power system.

Question 2
Electrical current may flow across the contacts of ____ to ____ electrical switches before it
reaches the consumer.
A) 1 to 5
B) 10 to 20
C) 25 to 50
D) 50 to 100
Correct Answer: D) 50 to 100
Rationale: The path from the generator to the consumer is complex, involving numerous
substations and distribution points, each with its own set of switches for control and
protection.

Question 3
The __________ operation of electrical switches can pose a serious hazard to personnel and
cause destruction of expensive equipment.
A) routine
B) automatic
C) improper
D) emergency

,Correct Answer: C) improper
Rationale: Operating high-voltage switches incorrectly can create dangerous arcs, energize
equipment that should be de-energized, and cause catastrophic failures.

Question 4
Electrical __________ are installed in the path from the generator to the consumer to provide
reliability, flexibility, and safeguards.
A) transformers
B) conductors
C) insulators
D) switches
Correct Answer: D) switches
Rationale: Switches are the primary devices used to control the path of electricity, allowing
for sections to be taken out of service (safeguards), re-routing power (flexibility), and
isolating faults (reliability).

Question 5
Switching performed for maintenance, construction, cleaning, or testing is considered
__________ switching.
A) Routine
B) Automatic
C) Emergency
D) Unscheduled
Correct Answer: A) Routine
Rationale: Routine switching is planned, non-emergency work performed to allow for the
safe maintenance and upkeep of the power system.

Question 6
Automatic reclosers (ARs), Voltage Pickup Units (VPUs), and Automatic Transfer Switching
(ATSs) are all examples of __________ switching operations.
A) Routine
B) Automatic
C) Emergency

,D) Manual
Correct Answer: B) Automatic
Rationale: These are devices that operate on their own, without direct operator
intervention, to restore power or reconfigure a circuit in response to specific system
conditions.

Question 7
Switching performed by Operators in response to power outages and abnormal conditions such
as overloads is known as __________ switching.
A) Routine
B) Automatic
C) Emergency
D) Scheduled
Correct Answer: C) Emergency
Rationale: Emergency switching is unplanned and is performed to isolate a problem (like a
fault) and to restore service to as many customers as possible.

Question 8
Transformers and voltage regulators must be energized and de-energized using:
A) Disconnects
B) Fuses
C) Circuit breakers
D) Ground switches
Correct Answer: C) Circuit breakers
Rationale: Transformers and regulators draw significant current when energized
(inrush/magnetizing current). Only a circuit breaker is designed to safely handle making or
breaking these load currents.

Question 9
Which electrical switch is designed to open, close, and interrupt both normal and abnormal
values of current flow?
A) Disconnect
B) Fuse

, C) Ground switch
D) Circuit breaker
Correct Answer: D) Circuit breaker
Rationale: This is the primary function of a circuit breaker. It is built to safely interrupt the
large arcs created when breaking high-current circuits, including fault currents.

Question 10
Which type of switch is provided as a method of visually confirming that a circuit has been
disconnected from a source of energy?
A) Circuit breaker
B) Recloser
C) Disconnect
D) Relay
Correct Answer: C) Disconnect
Rationale: A disconnect switch creates a visible air gap in the circuit, providing a positive,
visual confirmation that the circuit is open and isolated, which is a critical safety
requirement.

Question 11
Disconnects are NOT designed to:
A) Isolate equipment.
B) Provide a visual open.
C) Interrupt current flow.
D) Energize a short bus.
Correct Answer: C) Interrupt current flow.
Rationale: Disconnects have no mechanism to extinguish the large electrical arc that would
be created if they were opened under load. Doing so would destroy the switch and endanger
the operator.

Question 12
During abnormal fault conditions, current can exceed the normal rating of a device by as much
as:
A) 2 to 3 times