VIRGINIA ALTERNATIVE ENERGY
SYSTEM CONTRACTING EXAMINATION
PREP QUESTIONS ANSWERS EXPERT
VERIFIED
◉ Question 122: What is the function of a solar combiner in a
photovoltaic system?
Option A: To split the DC power into multiple circuits
Option B: To aggregate current from multiple strings for easier
connection to the inverter
Option C: To convert AC to DC
Option D: To provide surge protection. Answer: Correct Answer: B -
To aggregate current from multiple strings for easier connection to
the inverter
Explanation: The solar combiner collects and combines current from
several strings, simplifying the overall wiring scheme.
◉ Question 123: Which electrical parameter is critical when
configuring PV modules in parallel?
Option A: Voltage
Option B: Current
,Option C: Frequency
Option D: Resistance. Answer: Correct Answer: B - Current
Explanation: In parallel connections, the currents of individual
strings add together, so managing current levels is essential.
◉ Question 124: What is the significance of module "power
tolerance" in PV systems?
Option A: It determines the module's physical durability
Option B: It indicates the range within which actual power output
may vary from the rated value
Option C: It defines the module's color variations
Option D: It measures the module's efficiency in low light. Answer:
Correct Answer: B - It indicates the range within which actual power
output may vary from the rated value
Explanation: Power tolerance specifies the allowable deviation from
the nominal power rating, affecting system performance predictions.
◉ Question 125: Which of the following is a common cause of
energy losses in a PV system?
Option A: Excessive inverter capacity
,Option B: Mismatch between module outputs
Option C: Uniform module orientation
Option D: Over-cleaning of panels. Answer: Correct Answer: B -
Mismatch between module outputs
Explanation: Mismatches between modules (due to shading or
manufacturing variances) can lead to energy losses in the system.
◉ Question 126: What does "system design optimization" aim to
achieve in a PV installation?
Option A: Minimizing installation time
Option B: Maximizing energy output and economic efficiency
Option C: Standardizing panel colors
Option D: Reducing the number of inverters. Answer: Correct
Answer: B - Maximizing energy output and economic efficiency
Explanation: Optimization involves selecting and configuring
components to achieve the best balance between energy production,
cost, and reliability.
◉ Question 127: Which calculation is necessary for determining the
proper tilt angle of PV panels?
, Option A: Electrical load calculation
Option B: Solar altitude angle calculation
Option C: Inverter capacity calculation
Option D: Module string configuration. Answer: Correct Answer: B -
Solar altitude angle calculation
Explanation: The tilt angle is derived from the solar altitude and
latitude, maximizing the panels' exposure to sunlight.
◉ Question 128: What is one of the challenges of installing PV
systems in areas with heavy snowfall?
Option A: Increased wiring complexity
Option B: Accumulation of snow reducing light absorption
Option C: Excessive inverter capacity
Option D: Overheating of modules. Answer: Correct Answer: B -
Accumulation of snow reducing light absorption
Explanation: Snow can cover PV panels, blocking sunlight and
thereby reducing the system's energy production.
◉ Question 129: Which of the following best describes "string
sizing" in the context of PV installations?
SYSTEM CONTRACTING EXAMINATION
PREP QUESTIONS ANSWERS EXPERT
VERIFIED
◉ Question 122: What is the function of a solar combiner in a
photovoltaic system?
Option A: To split the DC power into multiple circuits
Option B: To aggregate current from multiple strings for easier
connection to the inverter
Option C: To convert AC to DC
Option D: To provide surge protection. Answer: Correct Answer: B -
To aggregate current from multiple strings for easier connection to
the inverter
Explanation: The solar combiner collects and combines current from
several strings, simplifying the overall wiring scheme.
◉ Question 123: Which electrical parameter is critical when
configuring PV modules in parallel?
Option A: Voltage
Option B: Current
,Option C: Frequency
Option D: Resistance. Answer: Correct Answer: B - Current
Explanation: In parallel connections, the currents of individual
strings add together, so managing current levels is essential.
◉ Question 124: What is the significance of module "power
tolerance" in PV systems?
Option A: It determines the module's physical durability
Option B: It indicates the range within which actual power output
may vary from the rated value
Option C: It defines the module's color variations
Option D: It measures the module's efficiency in low light. Answer:
Correct Answer: B - It indicates the range within which actual power
output may vary from the rated value
Explanation: Power tolerance specifies the allowable deviation from
the nominal power rating, affecting system performance predictions.
◉ Question 125: Which of the following is a common cause of
energy losses in a PV system?
Option A: Excessive inverter capacity
,Option B: Mismatch between module outputs
Option C: Uniform module orientation
Option D: Over-cleaning of panels. Answer: Correct Answer: B -
Mismatch between module outputs
Explanation: Mismatches between modules (due to shading or
manufacturing variances) can lead to energy losses in the system.
◉ Question 126: What does "system design optimization" aim to
achieve in a PV installation?
Option A: Minimizing installation time
Option B: Maximizing energy output and economic efficiency
Option C: Standardizing panel colors
Option D: Reducing the number of inverters. Answer: Correct
Answer: B - Maximizing energy output and economic efficiency
Explanation: Optimization involves selecting and configuring
components to achieve the best balance between energy production,
cost, and reliability.
◉ Question 127: Which calculation is necessary for determining the
proper tilt angle of PV panels?
, Option A: Electrical load calculation
Option B: Solar altitude angle calculation
Option C: Inverter capacity calculation
Option D: Module string configuration. Answer: Correct Answer: B -
Solar altitude angle calculation
Explanation: The tilt angle is derived from the solar altitude and
latitude, maximizing the panels' exposure to sunlight.
◉ Question 128: What is one of the challenges of installing PV
systems in areas with heavy snowfall?
Option A: Increased wiring complexity
Option B: Accumulation of snow reducing light absorption
Option C: Excessive inverter capacity
Option D: Overheating of modules. Answer: Correct Answer: B -
Accumulation of snow reducing light absorption
Explanation: Snow can cover PV panels, blocking sunlight and
thereby reducing the system's energy production.
◉ Question 129: Which of the following best describes "string
sizing" in the context of PV installations?