NABCEP PV INSTALLATION PROFESSIONAL (PVIP)
NEWEST 2026 UPDATE — ACTUAL QUESTIONS &
CORRECT ANSWERS | ALREADY GRADED A+
Content covered (most tested areas): System design •
Electrical safety • NEC compliance • PV system components •
Grounding & bonding • Wiring methods • Array layout •
Inverters • Commissioning • Performance • Troubleshooting •
Roof mounting • Documentation • Codes & standards •
Energy storage basics
1. What is the primary purpose of a PV module bypass diode?
A. Increase voltage output
B. Prevent reverse current flow between strings
C. Protect cells from hot-spot heating during partial shading
D. Improve inverter efficiency
Answer: C. Protect cells from hot-spot heating during partial shading
Bypass diodes allow current to flow around shaded cells, preventing
overheating and damage.
2. Which NEC article primarily governs photovoltaic systems?
A. Article 250
B. Article 690
C. Article 705
D. Article 110
,Answer: B. Article 690
Article 690 contains specific requirements for solar photovoltaic
installations.
3. What is the typical output of a single silicon PV cell?
A. 0.5–0.6 volts DC
B. 1.5 volts DC
C. 12 volts DC
D. 24 volts DC
Answer: A. 0.5–0.6 volts DC
Individual cells produce about half a volt under standard test
conditions.
4. In grid-tied systems, the inverter’s main function is to:
A. Store energy
B. Convert DC to AC
C. Step down voltage
D. Track sun position
Answer: B. Convert DC to AC
Inverters convert panel-generated DC power into utility-compatible AC.
5. What does STC stand for?
A. Standard Temperature Conditions
B. Solar Test Configuration
, C. Standard Test Conditions
D. System Thermal Coefficient
Answer: C. Standard Test Conditions
STC specifies 1000 W/m² irradiance, 25°C cell temperature, and AM1.5
spectrum.
6. Which device protects conductors from overcurrent?
A. Disconnect switch
B. Combiner box
C. Fuse or circuit breaker
D. Inverter
Answer: C. Fuse or circuit breaker
Overcurrent devices interrupt excessive current to prevent overheating
and fire.
7. What is the purpose of grounding a PV system?
A. Increase power output
B. Stabilize voltage to earth and reduce shock risk
C. Reduce shading losses
D. Improve module efficiency
Answer: B. Stabilize voltage to earth and reduce shock risk
Grounding protects people and equipment from electrical faults.
8. A string inverter differs from a microinverter because it:
A. Connects to a single module only
, B. Converts AC to DC
C. Serves multiple modules in series
D. Eliminates need for wiring
Answer: C. Serves multiple modules in series
String inverters process power from an entire series string of panels.
9. Which factor most affects PV output on a clear day?
A. Wind speed
B. Module color
C. Solar irradiance
D. Mounting height
Answer: C. Solar irradiance
Sunlight intensity directly determines power production.
10. What is the function of a combiner box?
A. Convert AC to DC
B. Combine multiple strings into one output
C. Store battery energy
D. Provide cooling
Answer: B. Combine multiple strings into one output
It consolidates string outputs and houses protective devices.
11. Maximum power point tracking (MPPT) optimizes:
A. Module temperature
B. Voltage and current for maximum power
NEWEST 2026 UPDATE — ACTUAL QUESTIONS &
CORRECT ANSWERS | ALREADY GRADED A+
Content covered (most tested areas): System design •
Electrical safety • NEC compliance • PV system components •
Grounding & bonding • Wiring methods • Array layout •
Inverters • Commissioning • Performance • Troubleshooting •
Roof mounting • Documentation • Codes & standards •
Energy storage basics
1. What is the primary purpose of a PV module bypass diode?
A. Increase voltage output
B. Prevent reverse current flow between strings
C. Protect cells from hot-spot heating during partial shading
D. Improve inverter efficiency
Answer: C. Protect cells from hot-spot heating during partial shading
Bypass diodes allow current to flow around shaded cells, preventing
overheating and damage.
2. Which NEC article primarily governs photovoltaic systems?
A. Article 250
B. Article 690
C. Article 705
D. Article 110
,Answer: B. Article 690
Article 690 contains specific requirements for solar photovoltaic
installations.
3. What is the typical output of a single silicon PV cell?
A. 0.5–0.6 volts DC
B. 1.5 volts DC
C. 12 volts DC
D. 24 volts DC
Answer: A. 0.5–0.6 volts DC
Individual cells produce about half a volt under standard test
conditions.
4. In grid-tied systems, the inverter’s main function is to:
A. Store energy
B. Convert DC to AC
C. Step down voltage
D. Track sun position
Answer: B. Convert DC to AC
Inverters convert panel-generated DC power into utility-compatible AC.
5. What does STC stand for?
A. Standard Temperature Conditions
B. Solar Test Configuration
, C. Standard Test Conditions
D. System Thermal Coefficient
Answer: C. Standard Test Conditions
STC specifies 1000 W/m² irradiance, 25°C cell temperature, and AM1.5
spectrum.
6. Which device protects conductors from overcurrent?
A. Disconnect switch
B. Combiner box
C. Fuse or circuit breaker
D. Inverter
Answer: C. Fuse or circuit breaker
Overcurrent devices interrupt excessive current to prevent overheating
and fire.
7. What is the purpose of grounding a PV system?
A. Increase power output
B. Stabilize voltage to earth and reduce shock risk
C. Reduce shading losses
D. Improve module efficiency
Answer: B. Stabilize voltage to earth and reduce shock risk
Grounding protects people and equipment from electrical faults.
8. A string inverter differs from a microinverter because it:
A. Connects to a single module only
, B. Converts AC to DC
C. Serves multiple modules in series
D. Eliminates need for wiring
Answer: C. Serves multiple modules in series
String inverters process power from an entire series string of panels.
9. Which factor most affects PV output on a clear day?
A. Wind speed
B. Module color
C. Solar irradiance
D. Mounting height
Answer: C. Solar irradiance
Sunlight intensity directly determines power production.
10. What is the function of a combiner box?
A. Convert AC to DC
B. Combine multiple strings into one output
C. Store battery energy
D. Provide cooling
Answer: B. Combine multiple strings into one output
It consolidates string outputs and houses protective devices.
11. Maximum power point tracking (MPPT) optimizes:
A. Module temperature
B. Voltage and current for maximum power
