CA C-46 Solar Contractor Exam
Questions and Correct Answers
(Verified Answers) Plus Rationale 2027
Q&A| Instant Download Pdf
Section 1: Solar Energy Fundamentals and System Design
1. What is the primary function of a photovoltaic (PV) module?
A. To convert alternating current into direct current
B. To store electricity for nighttime use
C. To convert sunlight directly into electrical energy
D. To regulate the utility grid voltage
Rationale: Photovoltaic modules use semiconductor materials to
convert sunlight into direct-current electricity through the
,photovoltaic effect. They do not store energy, convert AC to DC as
their primary function, or independently regulate utility voltage.
2. Which semiconductor material is most commonly used in
conventional solar photovoltaic cells?
A. Copper
B. Silicon
C. Aluminum
D. Lead
Rationale: Silicon is the dominant semiconductor material used in
conventional PV cells. Its electrical properties allow photons to
generate charge carriers that can be collected as electrical current.
Copper and aluminum are commonly used as conductors, while lead is
not the primary semiconductor in conventional solar cells.
3. What is the approximate standard test condition (STC) irradiance
used for rating photovoltaic modules?
A. 500 W/m²
B. 800 W/m²
C. 1,000 W/m²
D. 1,500 W/m²
,Rationale: Standard test conditions use an irradiance of 1,000 watts
per square meter, a cell temperature of 25°C, and a specified
reference solar spectrum. These standardized conditions allow
manufacturers to compare module performance under consistent
laboratory conditions.
4. What does the term “solar irradiance” describe?
A. The total electricity produced by a solar system over one year
B. The instantaneous solar power received per unit area
C. The total battery capacity available for storage
D. The resistance of a photovoltaic circuit
Rationale: Solar irradiance is the power of solar radiation incident on
a surface per unit area, commonly expressed in watts per square
meter. Solar energy accumulated over time is called irradiation and is
commonly expressed in kilowatt-hours per square meter per day.
5. Which condition generally causes the greatest reduction in
photovoltaic output when a portion of a conventional series-
connected string is shaded?
A. A small increase in wind speed
B. A slight decrease in ambient humidity
, C. Partial shading of one or more modules
D. A modest increase in nighttime temperature
Rationale: Partial shading can significantly reduce the current
available from series-connected modules. Depending on the system
design and bypass-diode operation, shaded cells or modules can limit
string output and create localized heating risks. Wind and humidity
generally have much smaller direct effects on electrical output.
6. What is the purpose of a solar inverter in a typical grid-connected
PV system?
A. To increase the amount of sunlight reaching the modules
B. To store surplus electricity chemically
C. To convert DC electricity into AC electricity
D. To eliminate the need for overcurrent protection
Rationale: PV modules produce DC electricity, while most building
electrical distribution systems use AC. An inverter converts DC into AC
suitable for the intended loads or grid interconnection. It does not
replace required circuit protection or automatically provide energy
storage.
Questions and Correct Answers
(Verified Answers) Plus Rationale 2027
Q&A| Instant Download Pdf
Section 1: Solar Energy Fundamentals and System Design
1. What is the primary function of a photovoltaic (PV) module?
A. To convert alternating current into direct current
B. To store electricity for nighttime use
C. To convert sunlight directly into electrical energy
D. To regulate the utility grid voltage
Rationale: Photovoltaic modules use semiconductor materials to
convert sunlight into direct-current electricity through the
,photovoltaic effect. They do not store energy, convert AC to DC as
their primary function, or independently regulate utility voltage.
2. Which semiconductor material is most commonly used in
conventional solar photovoltaic cells?
A. Copper
B. Silicon
C. Aluminum
D. Lead
Rationale: Silicon is the dominant semiconductor material used in
conventional PV cells. Its electrical properties allow photons to
generate charge carriers that can be collected as electrical current.
Copper and aluminum are commonly used as conductors, while lead is
not the primary semiconductor in conventional solar cells.
3. What is the approximate standard test condition (STC) irradiance
used for rating photovoltaic modules?
A. 500 W/m²
B. 800 W/m²
C. 1,000 W/m²
D. 1,500 W/m²
,Rationale: Standard test conditions use an irradiance of 1,000 watts
per square meter, a cell temperature of 25°C, and a specified
reference solar spectrum. These standardized conditions allow
manufacturers to compare module performance under consistent
laboratory conditions.
4. What does the term “solar irradiance” describe?
A. The total electricity produced by a solar system over one year
B. The instantaneous solar power received per unit area
C. The total battery capacity available for storage
D. The resistance of a photovoltaic circuit
Rationale: Solar irradiance is the power of solar radiation incident on
a surface per unit area, commonly expressed in watts per square
meter. Solar energy accumulated over time is called irradiation and is
commonly expressed in kilowatt-hours per square meter per day.
5. Which condition generally causes the greatest reduction in
photovoltaic output when a portion of a conventional series-
connected string is shaded?
A. A small increase in wind speed
B. A slight decrease in ambient humidity
, C. Partial shading of one or more modules
D. A modest increase in nighttime temperature
Rationale: Partial shading can significantly reduce the current
available from series-connected modules. Depending on the system
design and bypass-diode operation, shaded cells or modules can limit
string output and create localized heating risks. Wind and humidity
generally have much smaller direct effects on electrical output.
6. What is the purpose of a solar inverter in a typical grid-connected
PV system?
A. To increase the amount of sunlight reaching the modules
B. To store surplus electricity chemically
C. To convert DC electricity into AC electricity
D. To eliminate the need for overcurrent protection
Rationale: PV modules produce DC electricity, while most building
electrical distribution systems use AC. An inverter converts DC into AC
suitable for the intended loads or grid interconnection. It does not
replace required circuit protection or automatically provide energy
storage.
