NABCEP Cheat Sheet 2026

The 30 highest-yield NABCEP facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. Which NABCEP competency category specifically addresses the ability to evaluate roof structure for PV mounting load capacity? → Mechanical and Structural Design
2. Which energy efficiency measure typically has the shortest simple payback in residential buildings? → Air sealing accessible penetrations (attic, basement)
3. The 'fill factor' (FF) of a PV module is best described as: → The ratio of maximum power to the product of Voc and Isc
4. According to NEC 690.31(A), PV source and output circuits inside a building must be contained in which of the following? → Any listed wiring method suitable for the location
5. Why is documenting troubleshooting steps important? → To provide a record of actions taken for accountability and reference.
6. What is the minimum ground clearance required for unprotected PV wiring routed beneath a PV array on a roof per NEC 690.31? → Wiring must be enclosed in a listed wiring method
7. Which tool is most commonly used during commissioning to verify that each PV module in a string is producing power and to identify failed modules? → Thermal infrared camera
8. What is the primary purpose of conducting a Job Safety Analysis (JSA), also known as a Job Hazard Analysis (JHA), before beginning a PV installation task? → To proactively identify and control task-specific hazards.
9. Which instrument uses a fish-eye lens to photograph the sky dome and then analyzes the image to calculate solar access and shading fractions? → HemisView or SunEye device
10. According to NFPA 855, lithium-ion ESS installations exceeding 20 kWh in a Group B occupancy must be protected by which system? → Automatic sprinkler system complying with NFPA 13
11. What is the role of renewable energy sources in energy conservation? → They help conserve fossil fuels and reduce environmental impact.
12. IEEE 1547 is directly relevant to battery storage systems connected to the utility grid because it governs: → Distributed energy resource interconnection requirements
13. During solar installation, a worker is injured and misses 3 days of work. Under OSHA recordkeeping rules, this must be recorded on the OSHA 300 log as a: → Days-away-from-work case
14. What type of roof penetration sealant is recommended for PV mounting hardware to ensure a weatherproof installation? → Flashing kits with code-compliant waterproofing integrated into the mount
15. Under OSHA's Eye and Face Protection standard, safety glasses used on a PV job site must comply with which ANSI standard? → ANSI Z87.1
16. What is the minimum required fire setback distance from a ridge line for rooftop PV systems in many jurisdictions adopting IFC requirements? → 3 feet
17. Which federal law requires disclosure of potential environmental impacts before a large utility-scale solar project on federal land can proceed? → National Environmental Policy Act (NEPA)
18. A ground-mounted PV array is located in a region with a frost depth of 42 inches. What is the minimum embedment depth for the support posts? → Below the frost line
19. What wind exposure category would typically apply to a PV array installed on a building located in an open terrain with scattered obstructions? → Exposure C
20. A string of PV modules shows significantly lower output than adjacent strings on the same array. The first diagnostic step should be to: → Measure open-circuit voltage (Voc) of each module in the string
21. The Energy Use Intensity (EUI) of a building is expressed as: → BTU per square foot per year
22. Which UL standard specifically covers mounting systems (racks and rails) for PV modules? → UL 2703
23. Nominal Operating Cell Temperature (NOCT) is used to estimate module temperature under what conditions? → 800 W/m² irradiance, 20°C ambient, 1 m/s wind speed, open-circuit module
24. When inspecting a ground-mounted PV array, you observe rust staining on the mounting rails below the module clamps. What does this most likely indicate? → Galvanic corrosion between dissimilar metals at the clamp interface
25. A PV installer working on a scaffold must be protected from falls when the scaffold platform is at or above: → 10 feet
26. A transformer-less string inverter produces an audible high-pitched noise during operation but otherwise functions normally. What is the most likely source? → Switching frequency components from IGBT or MOSFET operation
27. Which fastener type is preferred for attaching aluminum racking to steel purlins in a commercial PV installation? → Stainless steel bolts
28. When NEC 690.31(B) permits PV system wiring to be installed in the same raceway as other systems, what condition must be met? → The conductors must be insulated for the maximum voltage of any conductor in the raceway
29. When calculating the maximum number of modules per string, the designer must consider the module's Voc at: → The lowest expected ambient temperature at the site
30. What is the typical lifespan of a solar panel? → 25-30 years.