TEXAS SOLAR ELECTRIC INSTALLER
CERTIFICATION EXAM ACTUAL 2026
VERIFIED QUESTIONS WITH ANSWERS
COMPREHENSIVE & RATIONALE|INSTANT
DOWNLOAD
1. A photovoltaic (PV) system designer is evaluating the ideal
orientation for a fixed-tilt solar array in central Texas to maximize
annual energy production. Which orientation generally provides
the highest yearly output?
A. Due east (90° azimuth)
B. Due south (180° azimuth)
C. Due west (270° azimuth)
D. Due north (0° azimuth)
Answer: B. Due south (180° azimuth)
Rationale: In the Northern Hemisphere, fixed PV arrays generally
achieve maximum annual energy production when facing true south.
East- or west-facing systems may improve morning or afternoon
production respectively but typically reduce total annual energy yield.
2. Which component converts direct current (DC) produced by
photovoltaic modules into alternating current (AC) suitable for
residential electrical systems?
A. Charge controller
B. Combiner box
C. Inverter
D. Disconnect switch
1
,Answer: C. Inverter
Rationale: The inverter transforms DC electricity generated by PV
modules into AC electricity compatible with household appliances and
utility grids. It also performs synchronization, monitoring, and
protective functions.
3. Under standard test conditions (STC), solar irradiance is defined
as:
A. 800 W/m²
B. 900 W/m²
C. 1000 W/m²
D. 1200 W/m²
Answer: C. 1000 W/m²
Rationale: Standard Test Conditions specify irradiance of 1000 W/m²,
cell temperature of 25°C, and air mass (AM) 1.5. Module ratings are
based on these laboratory conditions.
4. Which factor most significantly reduces photovoltaic module
voltage during summer afternoons in Texas?
A. Increased solar irradiance
B. Lower humidity
C. Higher cell temperature
D. Higher wind speed
Answer: C. Higher cell temperature
2
,Rationale: PV module voltage decreases as cell temperature increases.
Texas summers can substantially raise cell temperatures, reducing
operating voltage even when irradiance remains high.
5. What is the primary purpose of a Maximum Power Point Tracker
(MPPT)?
A. Increase module efficiency permanently
B. Store excess electricity
C. Optimize operating voltage and current
D. Cool photovoltaic modules
Answer: C. Optimize operating voltage and current
Rationale: MPPT continuously adjusts operating conditions so PV
modules produce maximum available power under changing irradiance
and temperature conditions.
6. A photovoltaic module has an open-circuit voltage (Voc) of 48
volts. Ten identical modules are connected in series. What is the
approximate total open-circuit voltage?
A. 48 V
B. 240 V
C. 480 V
D. 960 V
Answer: C. 480 V
Rationale: Series connections add voltage while current remains
constant. Therefore, 48 V × 10 = 480 V.
3
, 7. Which electrical quantity remains constant in a series-connected
PV string?
A. Voltage
B. Current
C. Power
D. Resistance
Answer: B. Current
Rationale: Current remains the same throughout a series circuit while
voltage is additive across components.
8. Which instrument is most appropriate for verifying solar irradiance
during commissioning?
A. Clamp ammeter
B. Pyranometer
C. Torque wrench
D. Megohmmeter
Answer: B. Pyranometer
Rationale: A pyranometer accurately measures incoming solar
radiation, allowing installers to compare expected and measured system
performance.
9. During rooftop installation, fall protection generally becomes
mandatory when workers are exposed to falls exceeding:
A. 2 feet
4
CERTIFICATION EXAM ACTUAL 2026
VERIFIED QUESTIONS WITH ANSWERS
COMPREHENSIVE & RATIONALE|INSTANT
DOWNLOAD
1. A photovoltaic (PV) system designer is evaluating the ideal
orientation for a fixed-tilt solar array in central Texas to maximize
annual energy production. Which orientation generally provides
the highest yearly output?
A. Due east (90° azimuth)
B. Due south (180° azimuth)
C. Due west (270° azimuth)
D. Due north (0° azimuth)
Answer: B. Due south (180° azimuth)
Rationale: In the Northern Hemisphere, fixed PV arrays generally
achieve maximum annual energy production when facing true south.
East- or west-facing systems may improve morning or afternoon
production respectively but typically reduce total annual energy yield.
2. Which component converts direct current (DC) produced by
photovoltaic modules into alternating current (AC) suitable for
residential electrical systems?
A. Charge controller
B. Combiner box
C. Inverter
D. Disconnect switch
1
,Answer: C. Inverter
Rationale: The inverter transforms DC electricity generated by PV
modules into AC electricity compatible with household appliances and
utility grids. It also performs synchronization, monitoring, and
protective functions.
3. Under standard test conditions (STC), solar irradiance is defined
as:
A. 800 W/m²
B. 900 W/m²
C. 1000 W/m²
D. 1200 W/m²
Answer: C. 1000 W/m²
Rationale: Standard Test Conditions specify irradiance of 1000 W/m²,
cell temperature of 25°C, and air mass (AM) 1.5. Module ratings are
based on these laboratory conditions.
4. Which factor most significantly reduces photovoltaic module
voltage during summer afternoons in Texas?
A. Increased solar irradiance
B. Lower humidity
C. Higher cell temperature
D. Higher wind speed
Answer: C. Higher cell temperature
2
,Rationale: PV module voltage decreases as cell temperature increases.
Texas summers can substantially raise cell temperatures, reducing
operating voltage even when irradiance remains high.
5. What is the primary purpose of a Maximum Power Point Tracker
(MPPT)?
A. Increase module efficiency permanently
B. Store excess electricity
C. Optimize operating voltage and current
D. Cool photovoltaic modules
Answer: C. Optimize operating voltage and current
Rationale: MPPT continuously adjusts operating conditions so PV
modules produce maximum available power under changing irradiance
and temperature conditions.
6. A photovoltaic module has an open-circuit voltage (Voc) of 48
volts. Ten identical modules are connected in series. What is the
approximate total open-circuit voltage?
A. 48 V
B. 240 V
C. 480 V
D. 960 V
Answer: C. 480 V
Rationale: Series connections add voltage while current remains
constant. Therefore, 48 V × 10 = 480 V.
3
, 7. Which electrical quantity remains constant in a series-connected
PV string?
A. Voltage
B. Current
C. Power
D. Resistance
Answer: B. Current
Rationale: Current remains the same throughout a series circuit while
voltage is additive across components.
8. Which instrument is most appropriate for verifying solar irradiance
during commissioning?
A. Clamp ammeter
B. Pyranometer
C. Torque wrench
D. Megohmmeter
Answer: B. Pyranometer
Rationale: A pyranometer accurately measures incoming solar
radiation, allowing installers to compare expected and measured system
performance.
9. During rooftop installation, fall protection generally becomes
mandatory when workers are exposed to falls exceeding:
A. 2 feet
4
