Examination Solar with Practice Questions
And Correct Answe
1. A California solar contractor is preparing a bid for a 10 kW residential PV system.
The CSLB requires a specific disclosure in the contract regarding the down payment.
Which of the following best describes the maximum allowable down payment for a
home improvement contract under California law?
A. 10% of the contract price or $1,000, whichever is less
B. 10% of the contract price or $1,000, whichever is greater
C. 20% of the contract price or $2,000, whichever is less
D. No down payment is allowed for solar contracts
Answer: A. 10% of the contract price or $1,000, whichever is less
Rationale: Under California Business and Professions Code §7159.5, the down payment
for a home improvement contract cannot exceed 10% of the contract price or $1,000,
whichever is less. Options B, C, and D are incorrect because they misstate the statutory
limit or incorrectly claim no down payment is allowed.
2. A solar PV system is being designed with a 7.6 kW inverter and a 10 kW DC array.
Per NEC 690.8, what is the maximum continuous output current for the inverter if its
rated output is 240V AC?
A. 31.7 A
B. 40.0 A
C. 25.3 A
D. 38.0 A
Answer: A. 31.7 A
Rationale: The inverter's continuous output current is calculated as 7600W / 240V =
31.67A, which is the maximum continuous output. NEC 690.8 requires this to be used for
conductor and overcurrent sizing. Options B, C, and D are incorrect because they either
use the DC array size or misapply the calculation.
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,3. During a roof-mounted solar installation, the structural engineer must verify that
the roof can support the additional load. Which factor is most critical in determining
the additional dead load per square foot for a ballasted system?
A. The weight of the PV modules and mounting hardware only
B. The weight of the ballast blocks plus the modules and mounting hardware
C. The wind uplift forces only
D. The live load of maintenance personnel
Answer: B. The weight of the ballast blocks plus the modules and mounting hardware
Rationale: For ballasted systems, the dead load includes the weight of the ballast blocks,
modules, and mounting hardware. Wind uplift is a separate lateral force, and live load is
not part of dead load. Options A, C, and D are incomplete or incorrect.
4. A solar contractor is installing a system in a region with high wind speeds.
According to ASCE 7-16, which parameter is used to determine the design wind
pressure on a solar array?
A. Basic wind speed and exposure category
B. Seismic zone factor
C. Soil bearing capacity
D. Snow load
Answer: A. Basic wind speed and exposure category
Rationale: ASCE 7-16 uses basic wind speed and exposure category to calculate design
wind pressure. Seismic zone factor is for earthquakes, soil bearing is for foundations, and
snow load is a separate consideration. Options B, C, and D are irrelevant to wind design.
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,5. A solar contractor is calculating the payback period for a commercial PV system.
The system costs $500,000, has an annual energy production of 750,000 kWh, and the
utility rate is $0.15/kWh. Assuming no incentives, what is the simple payback period?
A. 4.4 years
B. 5.0 years
C. 3.3 years
D. 6.7 years
Answer: A. 4.4 years
Rationale: Annual savings = 750,000 kWh × $0.15 = $112,500. Payback = $500,000 /
$112,500 = 4.44 years. Options B, C, and D result from miscalculations or use of incorrect
rates.
6. When installing a solar PV system on a commercial roof, which OSHA standard
specifically addresses fall protection requirements for workers?
A. OSHA 1910.269
B. OSHA 1926.501
C. OSHA 1910.147
D. OSHA 1926.405
Answer: B. OSHA 1926.501
Rationale: OSHA 1926.501 covers fall protection in construction, including requirements
for roofs. 1910.269 is for electric power generation, 1910.147 is lockout/tagout, and
1926.405 is electrical wiring methods. Options A, C, and D are incorrect standards.
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, 7. A solar contractor is designing a system that will interconnect with a utility grid.
According to California Public Utilities Commission (CPUC) Rule 21, what is
required for a inverter to be approved for interconnection?
A. It must be certified to UL 1741 SA
B. It must have a manual disconnect only
C. It must be listed to UL 1703
D. It must have a 10-year warranty
Answer: A. It must be certified to UL 1741 SA
Rationale: Rule 21 requires inverters to be certified to UL 1741 SA (Supplement A) for
smart inverter functionality. UL 1703 is for PV modules, manual disconnect is not
sufficient, and warranty is not an interconnection requirement. Options B, C, and D are
incorrect.
8. A solar contractor is preparing a permit application for a residential PV system in
California. Which document is typically required to demonstrate compliance with the
California Building Code for structural adequacy?
A. A structural letter from a licensed engineer
B. A copy of the homeowner's insurance policy
C. A utility bill showing average usage
D. A solar panel datasheet
Answer: A. A structural letter from a licensed engineer
Rationale: A structural letter from a licensed engineer is often required to verify roof
structural adequacy. Insurance policy, utility bill, and panel datasheet do not address
structural compliance. Options B, C, and D are not sufficient.
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