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Which of the following voltages should be included on the dc disconnected label to indicate MAXIMUM system voltage?
A 15 kW system has a total derate factor of 0.90. After 5 years, output drops by 2% annually due to degradation. What is the AC output in year 5?
An installer is sizing conductors for a 200-foot PV source circuit with a current of 8A at 400V DC. The design specifies a 1.5% voltage drop using copper wire at 30°C. What is the minimum wire size required?
According to the 2020 National Electrical Code (NEC), what is the minimum required working clearance in front of a 1000V DC PV inverter installed in a non-dwelling unit?
A PV system equipped with rapid shutdown requires a label stating ‘’RAPID SHUTDOWN SWITCH FOR SOLAR PV SYSTEM’’.
Which is the BEST description of where this label is required?
A PV module has a NOCT of 47°C. At 1000 W/m² and 35°C ambient, what is the cell temperature?
A 15 kW array has a PR of 0.88 and 1600 kWh/m²/year insolation. What is the annual output?
A PV array’s tilt is 15° at a latitude of 35°N. What is the annual energy loss compared to optimal tilt?
A technician has been called to a scale due to a low-performing array. The technician will perform tests in the 24-source circuit combiner box. After putting on the correct PPE and turning off and performing lock.tagout of the inverted and combiner disconnect. Which is the next step to safely begin electrical testing in the combiner box?
A PV system is designed with a 48V battery bank and a 5 kW inverter. The load requires 20 kWh/day, and the system must have 2 days of autonomy with a maximum depth of discharge (DoD) of 50%. What is the minimum battery capacity required in Ah?
A PV system operates at 800V DC. What is the minimum distance for unqualified personnel per NFPA 70E restricted approach boundary?
A PV system interconnects at a 480V three-phase service. The inverter output current is 20A per phase. What is the minimum size of the equipment grounding conductor (EGC) per NEC 250.122 if the OCPD is 30A?
A PV module shows burn marks near the junction box. What is the most likely cause?
A PV array is installed with a rapid shutdown system per NEC 690.12. The array is 15 feet from the service entrance. What is the maximum voltage allowed within the array boundary 30 seconds after shutdown initiation?
How should stratification be eliminated in a set of large, stationary, stationary flooded lead-acid batteries?
A PV system designer is selecting an inverter for a 12 kW array with a maximum power point voltage range of 300-450V DC. Which inverter specification is most critical to verify compatibility?
A ground-mount array uses driven piles with a lateral load capacity of 500 lbs. The wind load calculation yields a lateral force of 600 lbs per pile. What must be done?
A site has a known magnetic declination of 14 west. What should the corrected azimuth reading of the array be in order to be facing true south?
A PV system’s inverter displays a ground-fault error. What is the first troubleshooting step?
What is the maximum allowable voltage drop for a PV source circuit conductor run of 100 feet, using 10 AWG copper wire, if the system operates at 48V DC and the design specifies a 2% voltage drop?
A commercial 600v carport-mounted PV system is installed with rigid running under the parking lot to an inverter pad located at the edge of the parking lot. At what depth below the parking lot base MUST condult be buried?
A bank of batteries with capability of supplying 250A and a maximum voltage of 325V is housed in a concrete structure in a very humid location. There is service access alsie between rows of batteries. What is the REQUIRED safety distance between the rows of batteries.
A bifacial array gains 15% additional power from rear-side irradiance. If the front-side output is 10 kW, what is the total output?
Which of the following MUST be referenced for determining a site’s design wind speed?
A PV system was installed in July 2017 under the 2017 NEC. The system has a string inverter located inside a garage on a wall 10 ft, from the outside wall and 1oft, from the ac load center at the point of utility connection. The PV system has a PV array on the roof. Which of the following represents the PV rapid shutdown system requirement for the controlled PV system conductors associated with this PV array?
A PV system has a 1000V DC array feeding a transformerless inverter. What is the minimum insulation rating for the DC conductors per NEC 690.35?
A PV system produces 12,000 kWh annually at a site with 1500 kWh/m²/year insolation. The array area is 50 m². What is the system efficiency?
A project is using a PV module with a 25-38dc maximum power voltage range and a single input inverter with an operating windows of 250vdc-450dc. The dwelling the system is to be installed on has a 5:12 roof with a southeastem face that can accommodate 14 modules and southwestern face that can accommodate 10 modules. What is the MAXIMUM number of modules that can be installed for proper inverter maximum power point tracking?
A homeowner is weighing the PV module options for a roof-mounted solar array. Which is a correct option to present to the homeowner?
Which electrical connection requires the use of a torque device to complete the connection per NEC requirements?
A ground-mount PV system is planned for a site with a soil bearing capacity of 2000 psf. The array footing design requires a minimum bearing pressure of 1500 psf. What is the safety factor for this installation?
A module’s STC power is 300W, with a temperature coefficient of -0.40%/°C. At 65°C, what is the power loss percentage?
A metal condult containing an array circuit with Vmo of 400Vdc is connected to a metal enclosure at the location where the concentric knockouts have been punched by the manufacturer. Which method of attachment should be used?
A grid-interactive PV system with battery backup is being installed with a ground-mounted PV array located 200 ft, from the inverter and batteries. The dc PV output circuit has overcuit has overcurrent protection rated from 30A. To reduce voltage drop between the array and batteries, the output circuit wire size was determined to be 6 AWG. The fused dc disconnect between the inverted and batteries is rated for 300A. What is the required size of the equipment grounding conductor between the metal battery case and the inverter?
A ground-fault protection device (GFPD) trips during commissioning. What is the most likely cause per NEC 690.5?
A PV system is installed in a location with an average annual ambient temperature of 30°C. If the module’s NOCT (Nominal Operating Cell Temperature) is 45°C, what is the expected cell temperature under standard operating conditions (800 W/m² irradiance)?
When commissioning a PV system, which test is most critical to verify proper operation of the array before connecting to the inverter?
A PV technician is installing a 6.5KWac inverter using a 40A backfed breaker. The single line shows a 200A panelboard with a 200A breaker, but the installer finds that the panelbord actually has a 150A main breaker. Which of the following is the CORRECT installation option?
A PV system requires labeling per NEC 690.56. Which of the following must be posted at the point of interconnection?
According to the NEC, where on a residential PV system MUST the labeling describing the type of rapid shutdown be located?
A 20 kW array has a measured output of 16 kW at 800 W/m² irradiance. What is the performance loss due to irradiance?
An installer is terminating PV conductors in a combiner box. What is the minimum torque specification for a 10 AWG connection if not specified by the manufacturer?
An installer troubleshooting a ground-mounted array finds It to be performing as expected most of the time, but a ground-fault error is indicated on hot days. The inverter is in a shaded location. Which of the following should the installer check for FIRST when troubleshooting this array?
TESTED 01 May 2026