Arkansas AR-BESS Battery
Energy Storage Contractor
Practice Exam | Questions,
Verified Answers & Detailed
Rationales | Complete Contractor
License Exam Prep Study Guide |
Updated 2026
1. What is the primary function of a Battery Energy
Storage System (BESS)?
A. To generate electricity from fuel
B. To permanently replace the utility grid
C. To store electrical energy and release it when needed
D. To increase the frequency of the utility
Correct Answer: To store electrical energy and release it
when needed
Rationale: A BESS stores electrical energy, commonly in
batteries, and later discharges that energy for backup
power, load shifting, peak reduction, grid support, or
other applications.
2. Which NEC article specifically addresses Energy
Storage Systems?
A. Article 110
B. Article 250
C. Article 690
D. Article 706
Correct Answer: Article 706
,Rationale: NEC Article 706 contains requirements
specifically addressing Energy Storage Systems,
including ESS installation and associated equipment.
3. What is the main purpose of an Energy Storage
System disconnecting means?
A. Increase battery voltage
B. Increase battery capacity
C. Provide a means to disconnect the ESS from
associated circuits
D. Prevent all battery degradation
Correct Answer: Provide a means to disconnect the ESS
from associated circuits
Rationale: Disconnecting means allow equipment and
circuits to be isolated for operation, maintenance,
emergency response, or servicing.
4. Which battery chemistry is widely used in modern
stationary BESS installations?
A. Carbon-zinc
B. Alkaline
C. Lithium-ion
D. Mercury oxide
Correct Answer: Lithium-ion
Rationale: Lithium-ion technology is widely used
because of its high energy density, efficiency, power
capability, and commercially available battery-
management systems.
5. What does SOC stand for in battery terminology?
A. System Output Current
B. Safety Operating Circuit
,C. State of Charge
D. Storage Overcurrent Capacity
Correct Answer: State of Charge
Rationale: State of Charge represents the amount of
usable stored energy remaining in a battery relative to
its usable capacity.
6. What does BMS stand for?
A. Battery Main Switch
B. Backup Management Supply
C. Battery Management System
D. Battery Monitoring Standard
Correct Answer: Battery Management System
Rationale: The BMS monitors and manages battery
parameters such as voltage, temperature, current, state
of charge, and protective limits.
7. What is a primary function of a BMS?
A. Generate utility power
B. Monitor battery conditions and provide protective
controls
C. Replace the service disconnect
D. Eliminate all electrical hazards
Correct Answer: Monitor battery conditions and provide
protective controls
Rationale: A BMS can detect abnormal conditions and
initiate protective actions such as reducing current,
opening contactors, or shutting down the battery
system.
8. What is thermal runaway?
, A. Normal battery charging
B. A decrease in battery temperature
C. An uncontrolled self-heating process that can escalate
rapidly
D. A normal inverter operating condition
Correct Answer: An uncontrolled self-heating process
that can escalate rapidly
Rationale: Thermal runaway can result from internal
faults, overheating, overcharging, physical damage, or
other conditions and can lead to fire or hazardous gas
release.
9. What is the purpose of UL 9540?
A. Electrical worker licensing
B. Utility rate regulation
C. Evaluation of Energy Storage Systems and equipment
D. Transformer oil testing only
Correct Answer: Evaluation of Energy Storage Systems
and equipment
Rationale: UL 9540 is a safety standard covering Energy
Storage Systems and equipment, including system-level
safety considerations.
10. What does UL 9540A primarily address?
A. Contractor licensing
B. Battery capacity measurement only
C. Test methods for evaluating thermal runaway fire
propagation characteristics
D. Conductor ampacity
Correct Answer: Test methods for evaluating thermal
runaway fire propagation characteristics
Energy Storage Contractor
Practice Exam | Questions,
Verified Answers & Detailed
Rationales | Complete Contractor
License Exam Prep Study Guide |
Updated 2026
1. What is the primary function of a Battery Energy
Storage System (BESS)?
A. To generate electricity from fuel
B. To permanently replace the utility grid
C. To store electrical energy and release it when needed
D. To increase the frequency of the utility
Correct Answer: To store electrical energy and release it
when needed
Rationale: A BESS stores electrical energy, commonly in
batteries, and later discharges that energy for backup
power, load shifting, peak reduction, grid support, or
other applications.
2. Which NEC article specifically addresses Energy
Storage Systems?
A. Article 110
B. Article 250
C. Article 690
D. Article 706
Correct Answer: Article 706
,Rationale: NEC Article 706 contains requirements
specifically addressing Energy Storage Systems,
including ESS installation and associated equipment.
3. What is the main purpose of an Energy Storage
System disconnecting means?
A. Increase battery voltage
B. Increase battery capacity
C. Provide a means to disconnect the ESS from
associated circuits
D. Prevent all battery degradation
Correct Answer: Provide a means to disconnect the ESS
from associated circuits
Rationale: Disconnecting means allow equipment and
circuits to be isolated for operation, maintenance,
emergency response, or servicing.
4. Which battery chemistry is widely used in modern
stationary BESS installations?
A. Carbon-zinc
B. Alkaline
C. Lithium-ion
D. Mercury oxide
Correct Answer: Lithium-ion
Rationale: Lithium-ion technology is widely used
because of its high energy density, efficiency, power
capability, and commercially available battery-
management systems.
5. What does SOC stand for in battery terminology?
A. System Output Current
B. Safety Operating Circuit
,C. State of Charge
D. Storage Overcurrent Capacity
Correct Answer: State of Charge
Rationale: State of Charge represents the amount of
usable stored energy remaining in a battery relative to
its usable capacity.
6. What does BMS stand for?
A. Battery Main Switch
B. Backup Management Supply
C. Battery Management System
D. Battery Monitoring Standard
Correct Answer: Battery Management System
Rationale: The BMS monitors and manages battery
parameters such as voltage, temperature, current, state
of charge, and protective limits.
7. What is a primary function of a BMS?
A. Generate utility power
B. Monitor battery conditions and provide protective
controls
C. Replace the service disconnect
D. Eliminate all electrical hazards
Correct Answer: Monitor battery conditions and provide
protective controls
Rationale: A BMS can detect abnormal conditions and
initiate protective actions such as reducing current,
opening contactors, or shutting down the battery
system.
8. What is thermal runaway?
, A. Normal battery charging
B. A decrease in battery temperature
C. An uncontrolled self-heating process that can escalate
rapidly
D. A normal inverter operating condition
Correct Answer: An uncontrolled self-heating process
that can escalate rapidly
Rationale: Thermal runaway can result from internal
faults, overheating, overcharging, physical damage, or
other conditions and can lead to fire or hazardous gas
release.
9. What is the purpose of UL 9540?
A. Electrical worker licensing
B. Utility rate regulation
C. Evaluation of Energy Storage Systems and equipment
D. Transformer oil testing only
Correct Answer: Evaluation of Energy Storage Systems
and equipment
Rationale: UL 9540 is a safety standard covering Energy
Storage Systems and equipment, including system-level
safety considerations.
10. What does UL 9540A primarily address?
A. Contractor licensing
B. Battery capacity measurement only
C. Test methods for evaluating thermal runaway fire
propagation characteristics
D. Conductor ampacity
Correct Answer: Test methods for evaluating thermal
runaway fire propagation characteristics
