BREAKERS, DISCONNECTS, TRANSFORMERS) | ALL QUESTIONS AND CORRECT
ANSWERS | BRAND NEW VERSION!
Question 1
What is considered one of the primary and most critical tasks of an Electric Station Operator?
A) Cleaning station windows
B) Customer billing inquiries
C) The switching of high voltage circuits
D) General landscaping of the substation
E) Repairing residential light switches
Correct Answer: C) The switching of high voltage circuits
Rationale: According to the LADWP study material, the primary function of a Station
Operator is the safe manipulation and switching of high-voltage electrical circuits to
maintain system reliability and facilitate maintenance.
Question 2
Electrical current may flow across the contacts of how many electrical switches before it reaches
the consumer?
A) 1 to 5
B) 10 to 20
C) 50 to 100
D) Exactly 500
E) Only one
Correct Answer: C) 50 100
Rationale: Current travels through a vast network. It can pass through 50 to 100 different
switches between the point of generation and the final consumer, making the correct
operation of each switch vital.
Question 3
What is a potential consequence of the "improper" operation of electrical switches?
A) Lower monthly utility bills
B) Serious hazard to personnel and destruction of expensive equipment
C) Increased efficiency of the generator
D) Automatic cleaning of the dielectric medium
E) Permanent stabilization of the magnetic field
Correct Answer: B) Serious hazard to personnel and destruction of expensive equipment
Rationale: Incorrect switching can lead to catastrophic equipment failure, severe injury or
death to operators, and widespread power outages for consumers.
Question 4
Why are electrical switches installed in the path from the generator to the consumer?
A) To increase the cost of electricity
B) To provide reliability, flexibility, and safeguards
, 2
C) To allow current to flow uncontrolled
D) To reduce the number of transformers needed
E) To prevent the use of magnetic induction
Correct Answer: B) To provide reliability, flexibility, and safeguards
Rationale: Switches allow the power system to be reconfigured for maintenance or in
response to trouble, ensuring that power can be routed around problems and keeping the
system protected.
Question 5
Which type of switching is performed specifically for maintenance, construction, cleaning, or
testing?
A) Emergency switching
B) Automatic switching
C) Routine switching
D) Secondary switching
E) Magnetizing switching
Correct Answer: C) Routine
Rationale: Routine switching is scheduled work designed to isolate equipment for non-
emergency reasons like construction or periodic maintenance.
Question 6
Automatic reclosers (ARs) and Voltage Pickup Units (VPUs) are examples of which category of
switching?
A) Routine switching
B) Manual hook-stick switching
C) Automatic switching
D) High-side only switching
E) Copper loss switching
Correct Answer: C) Automatic
Rationale: Automatic switching operations are pre-programmed actions taken by the
system (like reclosers or transfer switches) without immediate operator intervention.
Question 7
What type of switching operation includes "4.8kV Ground Searches" and "Restoration"?
A) Routine switching
B) Emergency switching
C) Non-conductive switching
D) Passive switching
E) Hysteresis switching
Correct Answer: B) Emergency
, 3
Rationale: Emergency switching is done in response to abnormal conditions, faults, or
outages to restore service and isolate trouble areas.
Question 8
What is the primary benefit of the strategic placement of electrical switches throughout the
power system?
A) It increases the voltage at the consumer's house
B) It makes the equipment more expensive to maintain
C) It limits both the duration and the extent of power outages
D) It eliminates the need for circuit breakers
E) It creates more heat in the conductors
Correct Answer: C) It limits both the duration and the extent of power outages
Rationale: Strategic switch placement allows operators to isolate only the faulted portion of
a circuit, keeping as many customers in service as possible during a disturbance.
Question 9
The electrical function of switches falls into two main categories: manipulation under load and
__________.
A) Increasing the frequency of the system
B) Measuring the resistance of the core
C) Providing a visual confirmation of de-energization
D) Automatic cleaning of the bushings
E) Generating magnetizing current
Correct Answer: C) providing a visual confirmation of de-energization.
Rationale: Operators use Load-interrupting devices (breakers) to stop current flow and
Disconnects to provide a visible gap, ensuring the circuit is truly safe for crews.
Question 10
Which device is used to manipulate high values of current and voltage in circuits that are
carrying current?
A) Disconnects
B) Hook-sticks
C) Circuit breakers
D) Potential transformers
E) Semaphore indicators
Correct Answer: C) Circuit breakers
Rationale: Circuit breakers are specifically designed to safely "break" the flow of electricity
even when the circuit is fully loaded or under fault conditions.
Question 11
When energizing or de-energizing transformers and voltage regulators, what must be used?