NABCEP PV System Inspector
Certification Practice Exam 100
Questions And Correct Answers
(Verified Answers) Plus Rationales
2026 Q&A Instant Download Pdf
1. What is the primary purpose of a PV system inspection?
A. To evaluate the aesthetic quality of the installation
B. To verify compliance with design, safety, and code standards
C. To provide tax incentives to the system owner
D. To check the warranty of modules
B. To verify compliance with design, safety, and code standards
The main role of a PV system inspector is to ensure that the system is installed
according to applicable codes, standards, and design specifications,
protecting both the system owner and the public.
2. Which NEC article specifically covers photovoltaic systems?
A. Article 110
B. Article 690
C. Article 705
D. Article 250
B. Article 690
,NEC Article 690 specifically addresses photovoltaic systems, including wiring
methods, grounding, and installation requirements.
3. A PV module's nameplate rating is measured at Standard Test Conditions
(STC). What are the STC parameters?
A. 800 W/m² irradiance, 20°C cell temperature
B. 1000 W/m², 25°C ambient temperature
C. 1000 W/m² irradiance, 25°C cell temperature, AM 1.5 spectrum
D. 1200 W/m², 30°C cell temperature
C. 1000 W/m² irradiance, 25°C cell temperature, AM 1.5 spectrum
Standard Test Conditions (STC) use 1000 W/m² irradiance, 25°C cell
temperature, and Air Mass 1.5 spectrum to provide a consistent baseline for
module ratings.
4. What is the primary purpose of a PV system disconnect?
A. Increase system voltage
B. Provide a means to safely isolate the PV system for maintenance or
emergency
C. Enhance module performance
D. Reduce ground faults
B. Provide a means to safely isolate the PV system for maintenance or
emergency
PV disconnects provide safe isolation to protect personnel during
maintenance or emergencies.
5. Which device is used to prevent backfeeding into the utility grid during an
outage?
,A. Combiner box
B. Disconnect switch
C. Anti-islanding inverter
D. Grounding electrode
C. Anti-islanding inverter
Anti-islanding inverters automatically shut down to prevent feeding power
into the grid during an outage, enhancing safety for utility personnel.
6. When inspecting PV modules, what is a common sign of potential damage?
A. Dust accumulation
B. Cracks, delamination, or browning of cells
C. Minor water spots
D. Manufacturer label presence
B. Cracks, delamination, or browning of cells
Visible physical damage like cracks or delamination may affect performance
and safety of PV modules.
7. What is the purpose of grounding a PV array?
A. Improve efficiency
B. Protect against electrical shock and lightning
C. Increase output voltage
D. Prevent module shading
B. Protect against electrical shock and lightning
Grounding ensures that exposed conductive parts do not pose a shock hazard
and helps protect against lightning and faults.
, 8. Which inspection tool is commonly used to measure insulation resistance?
A. Clamp meter
B. Multimeter
C. Megohmmeter (insulation resistance tester)
D. Thermocouple
C. Megohmmeter (insulation resistance tester)
A megohmmeter measures insulation resistance to verify that wiring and
components are safe from leakage currents.
9. Which NEC requirement applies to overcurrent protection in a PV system?
A. Article 250
B. Article 690.9
C. Article 705
D. Article 200
B. Article 690.9
NEC 690.9 covers the sizing and requirements of overcurrent protection for PV
source and output circuits.
10. What device protects a PV system from reverse current at night?
A. Charge controller
B. Fuse holder
C. Blocking diode
D. Ground rod
C. Blocking diode
Blocking diodes prevent current from flowing backward through modules at
night when the array voltage drops below battery or grid voltage.
Certification Practice Exam 100
Questions And Correct Answers
(Verified Answers) Plus Rationales
2026 Q&A Instant Download Pdf
1. What is the primary purpose of a PV system inspection?
A. To evaluate the aesthetic quality of the installation
B. To verify compliance with design, safety, and code standards
C. To provide tax incentives to the system owner
D. To check the warranty of modules
B. To verify compliance with design, safety, and code standards
The main role of a PV system inspector is to ensure that the system is installed
according to applicable codes, standards, and design specifications,
protecting both the system owner and the public.
2. Which NEC article specifically covers photovoltaic systems?
A. Article 110
B. Article 690
C. Article 705
D. Article 250
B. Article 690
,NEC Article 690 specifically addresses photovoltaic systems, including wiring
methods, grounding, and installation requirements.
3. A PV module's nameplate rating is measured at Standard Test Conditions
(STC). What are the STC parameters?
A. 800 W/m² irradiance, 20°C cell temperature
B. 1000 W/m², 25°C ambient temperature
C. 1000 W/m² irradiance, 25°C cell temperature, AM 1.5 spectrum
D. 1200 W/m², 30°C cell temperature
C. 1000 W/m² irradiance, 25°C cell temperature, AM 1.5 spectrum
Standard Test Conditions (STC) use 1000 W/m² irradiance, 25°C cell
temperature, and Air Mass 1.5 spectrum to provide a consistent baseline for
module ratings.
4. What is the primary purpose of a PV system disconnect?
A. Increase system voltage
B. Provide a means to safely isolate the PV system for maintenance or
emergency
C. Enhance module performance
D. Reduce ground faults
B. Provide a means to safely isolate the PV system for maintenance or
emergency
PV disconnects provide safe isolation to protect personnel during
maintenance or emergencies.
5. Which device is used to prevent backfeeding into the utility grid during an
outage?
,A. Combiner box
B. Disconnect switch
C. Anti-islanding inverter
D. Grounding electrode
C. Anti-islanding inverter
Anti-islanding inverters automatically shut down to prevent feeding power
into the grid during an outage, enhancing safety for utility personnel.
6. When inspecting PV modules, what is a common sign of potential damage?
A. Dust accumulation
B. Cracks, delamination, or browning of cells
C. Minor water spots
D. Manufacturer label presence
B. Cracks, delamination, or browning of cells
Visible physical damage like cracks or delamination may affect performance
and safety of PV modules.
7. What is the purpose of grounding a PV array?
A. Improve efficiency
B. Protect against electrical shock and lightning
C. Increase output voltage
D. Prevent module shading
B. Protect against electrical shock and lightning
Grounding ensures that exposed conductive parts do not pose a shock hazard
and helps protect against lightning and faults.
, 8. Which inspection tool is commonly used to measure insulation resistance?
A. Clamp meter
B. Multimeter
C. Megohmmeter (insulation resistance tester)
D. Thermocouple
C. Megohmmeter (insulation resistance tester)
A megohmmeter measures insulation resistance to verify that wiring and
components are safe from leakage currents.
9. Which NEC requirement applies to overcurrent protection in a PV system?
A. Article 250
B. Article 690.9
C. Article 705
D. Article 200
B. Article 690.9
NEC 690.9 covers the sizing and requirements of overcurrent protection for PV
source and output circuits.
10. What device protects a PV system from reverse current at night?
A. Charge controller
B. Fuse holder
C. Blocking diode
D. Ground rod
C. Blocking diode
Blocking diodes prevent current from flowing backward through modules at
night when the array voltage drops below battery or grid voltage.
