,LADWP Electrical Safety and Operations Exam Review 2026 | Verified
Q&A with Detailed Rationales – Los Angeles Department of Water &
Power Test Prep | Graded A+
Question 1
What is the primary purpose of a circuit breaker in an electrical
substation?
• A) To step up transmission voltage levels for long-distance
transport
• B) To safely interrupt both normal load currents and high fault
currents
• C) To provide a visible air gap for personnel confirmation of de-
energization
• D) To automatically balance phase loads across residential
distribution lines
Correct Answer: B
Detailed Rationale: Circuit breakers are heavy-duty switching devices
designed to close, carry, and interrupt currents under normal circuit
conditions, as well as automatically open under abnormal conditions
such as short circuits or overloads (fault currents) to protect
downstream equipment. Disconnect switches, rather than circuit
breakers, typically provide the visible air gap.
Question 2
,According to utility safety standards and OSHA 1910.269, who is
authorized to work on exposed energized circuits operating above 50
volts?
• A) Any standard company employee who has completed general
orientation
• B) Qualified Electrical Workers (QEWs) trained specifically in safety
and hazard mitigation
• C) General maintenance contractors without utility oversight
• D) Apprentices working entirely unsupervised on high-voltage
apparatus
Correct Answer: B
Detailed Rationale: Regulations strictly mandate that only Qualified
Electrical Workers (QEWs)—individuals who have received specific
training in recognizing and avoiding high-voltage electrical hazards,
minimum approach distances, and proper PPE use—may work on or
near exposed energized parts.
Question 3
What type of electrical switch is designed primarily to provide a safe,
visible physical break to confirm de-energization, but should not
typically be opened under heavy load unless specifically rated as a
load-break switch?
• A) SF6 Gas Circuit Breaker
• B) Vacuum Circuit Breaker
• C) Disconnect Switch (Air Switch)
, • D) Automatic Transfer Switch (ATS)
Correct Answer: C
Detailed Rationale: Standard air-break disconnect switches are isolating
devices meant to be operated after the circuit has been de-energized by
a circuit breaker. Opening them under load without a load-break rating
can draw a severe, destructive electric arc.
Question 4
What is the mandatory safety step required before beginning physical
maintenance on de-energized high-voltage lines or equipment to
protect against induced voltages and accidental re-energization?
• A) Installing temporary protective grounds
• B) Performing an acoustic insulation test
• C) Increasing the main transformer tap settings
• D) Clearing the localized SCADA alarm log history
Correct Answer: A
Detailed Rationale: Protective grounding is critical. Even when a line is
de-energized, capacitive coupling, induction from adjacent energized
lines, or accidental backfeed can introduce lethal voltages. Applying
protective grounds safely drains these currents to earth.
Question 5
Before starting any operational task on or near power generation,
transmission, or distribution facilities, what mandatory meeting must
the employee in charge conduct?
• A) Financial alignment review
Q&A with Detailed Rationales – Los Angeles Department of Water &
Power Test Prep | Graded A+
Question 1
What is the primary purpose of a circuit breaker in an electrical
substation?
• A) To step up transmission voltage levels for long-distance
transport
• B) To safely interrupt both normal load currents and high fault
currents
• C) To provide a visible air gap for personnel confirmation of de-
energization
• D) To automatically balance phase loads across residential
distribution lines
Correct Answer: B
Detailed Rationale: Circuit breakers are heavy-duty switching devices
designed to close, carry, and interrupt currents under normal circuit
conditions, as well as automatically open under abnormal conditions
such as short circuits or overloads (fault currents) to protect
downstream equipment. Disconnect switches, rather than circuit
breakers, typically provide the visible air gap.
Question 2
,According to utility safety standards and OSHA 1910.269, who is
authorized to work on exposed energized circuits operating above 50
volts?
• A) Any standard company employee who has completed general
orientation
• B) Qualified Electrical Workers (QEWs) trained specifically in safety
and hazard mitigation
• C) General maintenance contractors without utility oversight
• D) Apprentices working entirely unsupervised on high-voltage
apparatus
Correct Answer: B
Detailed Rationale: Regulations strictly mandate that only Qualified
Electrical Workers (QEWs)—individuals who have received specific
training in recognizing and avoiding high-voltage electrical hazards,
minimum approach distances, and proper PPE use—may work on or
near exposed energized parts.
Question 3
What type of electrical switch is designed primarily to provide a safe,
visible physical break to confirm de-energization, but should not
typically be opened under heavy load unless specifically rated as a
load-break switch?
• A) SF6 Gas Circuit Breaker
• B) Vacuum Circuit Breaker
• C) Disconnect Switch (Air Switch)
, • D) Automatic Transfer Switch (ATS)
Correct Answer: C
Detailed Rationale: Standard air-break disconnect switches are isolating
devices meant to be operated after the circuit has been de-energized by
a circuit breaker. Opening them under load without a load-break rating
can draw a severe, destructive electric arc.
Question 4
What is the mandatory safety step required before beginning physical
maintenance on de-energized high-voltage lines or equipment to
protect against induced voltages and accidental re-energization?
• A) Installing temporary protective grounds
• B) Performing an acoustic insulation test
• C) Increasing the main transformer tap settings
• D) Clearing the localized SCADA alarm log history
Correct Answer: A
Detailed Rationale: Protective grounding is critical. Even when a line is
de-energized, capacitive coupling, induction from adjacent energized
lines, or accidental backfeed can introduce lethal voltages. Applying
protective grounds safely drains these currents to earth.
Question 5
Before starting any operational task on or near power generation,
transmission, or distribution facilities, what mandatory meeting must
the employee in charge conduct?
• A) Financial alignment review
