NABCEP PV System Inspector

During an electrical inspection of a PV system, you observe that the AC interconnection point label is missing. According to NEC 690.54, what information must this label include?

• AThe nameplate data of the PV modules only
• BThe operating AC voltage, rated AC output current, maximum AC output current, and nominal…
• CThe utility company name and account number
• DOnly the rated AC output current of the inverter

What is the PRIMARY purpose of verifying that labels on a PV system are of sufficient durability for the environment involved?

• ATo confirm the labels were manufactured by a listed company
• BTo meet the aesthetic requirements of the building owner
• CTo ensure the labels match the contractor's branding requirements
• DTo ensure safety information remains legible throughout the life of the system despite we…

An inspector finds that DC raceway labels are not present on a residential PV installation. According to NEC 690.31(G), how must DC PV conduits be identified?

• AWith labels marked 'PHOTOVOLTAIC POWER SOURCE' at every accessible point and at intervals…
• BDC raceways do not require labeling if the conductors inside are properly colored
• CWith a single label at the inverter only
• DWith yellow paint every 20 feet

When inspecting a PV system, you notice the rapid shutdown system label is missing from the service entrance. What does NEC 690.12 require for rapid shutdown labeling?

• AA reflective label at the service entrance indicating the type of rapid shutdown system a…
• BOnly a label on the inverter is required
• CA label indicating the system does not have rapid shutdown capability
• DNo label is required if the system is less than 5 kW

What is the proper label color combination for a PV system danger/warning sign per ANSI Z535 standards?

• AWhite text on red background for DANGER or black text on orange background for WARNING
• BGreen text on yellow background
• CAny color combination chosen by the installer
• DBlue text on white background

During inspection, the main service panel label for the PV system is handwritten on a piece of tape. What is the correct inspector response?

• ARequire that labels be the proper color and in legible print, not handwritten, per NEC re…
• BRequire the installer to laminate the handwritten label
• CAccept it only if the handwriting is clearly legible
• DAccept it as long as the information is accurate

When verifying that installed PV components match the approved plans, what is a CRITICAL first step for the inspector?

• AChecking the color of the modules against the plan rendering
• BVerifying working clearances on all components and ensuring all components are listed, la…
• CCounting the number of PV modules to verify it matches the plan count
• DMeasuring the tilt angle of each module

An inspector discovers that an inverter installed outdoors is rated NEMA 1. What action should the inspector take?

• AFlag the installation as non-compliant because NEMA 1 enclosures are rated for indoor use…
• BRequest documentation that the manufacturer approved the outdoor installation
• CApprove the installation since NEMA 1 is suitable for all locations
• DApprove it if the inverter is under a roof overhang

What does it mean for a PV component to be 'listed' in the context of NEC requirements?

• AThe component appears on the installer's bill of materials
• BThe component is included in the manufacturer's product catalog
• CThe equipment has been evaluated by a Nationally Recognized Testing Laboratory (NRTL) and…
• DThe component has been approved by the local utility company

During inspection, you find that the number of PV modules installed differs from the approved plan by two additional modules. What is the appropriate response?

• AApprove it if the additional modules are the same manufacturer
• BApprove it as long as the string voltage does not exceed the inverter maximum
• CApprove the installation since more modules means more power
• DFail the inspection and require a revised permit application reflecting the actual instal…

When inspecting PV system conductors, what is the CRITICAL factor in determining if conductor ampacity is appropriate for the circuit?

• AThe conductor is copper rather than aluminum
• BThe conductor's ampacity after applying temperature correction and conduit fill adjustmen…
• CThe conductor has a voltage rating of at least 600V
• DThe conductor color matches the plan specifications

An inspector finds USE-2 cable being used in an exterior conduit run from the array to the inverter. Is this acceptable?

• ANo, USE-2 cable can never be used in PV systems
• BYes, as long as the conduit is weather-tight
• CNo, USE-2 is rated for direct burial and underground use only and cannot be used in condu…
• DYes, USE-2 is suitable for all applications including conduit

What is the required conductor voltage rating for PV source circuits operating at a maximum system voltage of 480V DC?

• A1000V for all PV systems regardless of voltage
• B600V minimum, or rated for the maximum system voltage, whichever is greater
• C300V minimum
• D480V exactly matching the system voltage

During a conduit fill inspection, an inspector counts 6 current-carrying conductors in a single conduit run. What conduit fill percentage is the maximum allowed per NEC Chapter 9, Table 1?

• A31% for over 2 conductors
• B60% regardless of the number of conductors
• C40% for more than 2 conductors
• D53% for 1-2 conductors

What must an inspector verify regarding conduit expansion joints on a long exterior conduit run for a PV system?

• AThat expansion joints are installed at every conduit coupling
• BThat expansion joints are installed at appropriate intervals based on the conduit materia…
• CThat expansion joints are only needed on runs exceeding 100 feet
• DThat expansion joints are not used on PV conduit runs

What color must an equipment grounding conductor (EGC) be if it is size 6 AWG or smaller?

• AAny color is acceptable if labeled at each end
• BAny color with green tape applied at terminations
• CWhite or gray
• DGreen, green with one or more yellow stripes, or bare

When inspecting raceway connections on a rooftop PV installation exposed to weather, which connection type is required?

• ARaintight or weatherproof connectors rated for the location
• BCompression connectors for indoor use
• CAny connector that physically fits the raceway
• DStandard set-screw type connectors

An inspector verifies that a PV system conductor termination uses a copper lug on an aluminum conductor. What is the concern?

• ADissimilar metals at the termination can cause galvanic corrosion, increased resistance,…
• BThe only concern is that copper lugs cost more than aluminum lugs
• CThere is no concern as long as the lug is properly torqued
• DAluminum conductors cannot be used in PV systems

What must an inspector verify about the torque applied to conductor terminations in a PV system?

• ATorque verification is not required for DC circuits
• BThat all connections use the same torque regardless of size
• CThat connections are made to the manufacturer's specified torque values as required by NE…
• DThat the connections feel tight when tugged by hand

A PV system termination uses a lug rated for 75 degrees C, but the conductor insulation is rated for 90 degrees C (THWN-2). What ampacity rating must be used for the conductor?

• AThe 90 degrees C column of NEC Table 310.16 since the insulation is 90 degrees C rated
• BThe 75 degrees C column of NEC Table 310.16, because the ampacity is limited by the lowes…
• CAn average of the 75 and 90 degree C ratings
• DThe 60 degrees C column to be conservative

When inspecting the grounding system of a PV installation, what is the FIRST thing an inspector should verify?

• AThat the grounding electrode conductor is painted green
• BThat the system uses a ground rod exclusively
• CThat the grounding wire is the largest conductor in the system
• DThat all exposed non-current-carrying metallic parts are properly bonded to the equipment…

What is the purpose of the grounding electrode conductor (GEC) in a PV system, and how does it differ from the equipment grounding conductor (EGC)?

• AThe GEC and EGC serve the same purpose and are interchangeable
• BThe EGC is larger than the GEC in all installations
• CThe GEC carries fault current and the EGC only provides lightning protection
• DThe GEC connects the system grounding point to the grounding electrode, while the EGC bon…

An inspector checks the inverter display and sees a ground fault indicator active. What should the inspector do?

• ADocument the ground fault indication, flag it as a critical safety concern, and recommend…
• BApprove the system if it is still producing power
• CReset the inverter to clear the fault
• DIgnore it since ground faults are common and self-clearing

For a PV system with a maximum circuit current of 40 amps, what is the minimum size equipment grounding conductor required per NEC Table 250.122?

• A8 AWG copper
• B6 AWG copper
• C14 AWG copper
• D10 AWG copper

What listed grounding methods are commonly used for bonding PV module frames to the racking system?

• ASoldered wire connections to the frame
• BStandard bolts and nuts without any special provisions
• CListed lay-in lugs, WEEB (Washer, Electrical Equipment Bond) clips, or other UL-listed bo…
• DSelf-tapping screws with wire wrapped around them

When inspecting the point of interconnection for a PV system connected to a 200A main breaker panel using a backfed breaker, what is the maximum PV breaker size allowed per the NEC 705.12(B)(2) 120% rule?

• AThe PV breaker can be up to the size where the sum of the PV breaker and the main breaker…
• B20% of the main breaker rating
• C40A
• DAny size up to the main breaker rating

An inspector verifies that a PV system backfed breaker is installed at the OPPOSITE end of the busbar from the main breaker. Why is this location required?

• AThe opposite end position is only a recommendation, not a requirement
• BIt is required only for aesthetic purposes
• CIt ensures that the busbar is not subjected to currents exceeding its rating at any point…
• DIt makes the breaker easier to access for maintenance

What must an inspector verify about the overcurrent protection device used for a supply-side interconnection per NEC 705.12(A)?

• AThat an overcurrent protection device is installed where the PV conductors connect to the…
• BThat only fuses can be used, not breakers
• CThat the OCPD is the same brand as the main panel
• DThat no overcurrent protection is needed for supply-side connections

What is the maximum current that can be fed to a 200A rated busbar when using a supply-side connection?

• A400A since supply-side connections double the busbar capacity
• BThere is no specific NEC limit on supply-side current as long as conductors are properly…
• C200A total from all sources combined
• D240A using the 120% rule

Per NEC 690.8(A), the maximum PV source circuit current used for conductor sizing is calculated as:

• AThe sum of the module Imp ratings in the string
• BThe sum of the parallel-connected module or string short-circuit currents (Isc)
• CThe inverter maximum input current rating
• DThe module Voc divided by the conductor resistance

What is the continuous duty multiplier required by NEC for sizing PV circuit conductors and overcurrent protection devices?

• A150% for safety margin
• B100% -- no multiplier is required
• C80% derating factor
• D125% -- conductors and OCPDs must be rated for at least 125% of the maximum circuit curre…

An inspector finds that 20A fuses are protecting a PV source circuit with a calculated maximum current of 9.5A. Is this compliant?

• ANo, the fuses are oversized and do not adequately protect the conductors
• BYes, because any fuse larger than the circuit current is acceptable
• CNo, fuses must exactly match the circuit current
• DYes, if the conductors are rated for at least 20A and the fuse rating is between 125% and…

When must overcurrent protection be provided for PV source circuits according to NEC 690.9?

• AAlways, for every PV source circuit regardless of configuration
• BWhen there are three or more parallel-connected strings, or when the available fault curr…
• COnly when the system exceeds 600V DC
• DOnly for commercial installations, not residential

What voltage limitation must an inspector verify for overcurrent protection devices in a PV DC circuit?

• AThe OCPD must have a DC voltage rating equal to or greater than the maximum system voltag…
• BThe OCPD voltage rating is only important for systems over 1000V
• CThe OCPD must be rated for at least 120V AC
• DAC-rated breakers can be used for DC circuits at any voltage

An inspector verifies the existing electrical distribution system before approving a PV interconnection. What characteristic is CRITICAL to confirm?

• AThat the available fault current, busbar rating, and main breaker rating can accommodate…
• BThe brand of the main panel
• CThe age of the electrical panel
• DWhether the panel has a main lug or main breaker configuration only

NEC 690.13 requires a PV system disconnecting means. Where must this disconnect be located?

• AIn a readily accessible location, at a site that is visible and not more than 6 feet from…
• BInside the main electrical panel only
• CAt the utility meter only
• DOnly on the roof near the array

What is the significance of the NEC 690.12 rapid shutdown requirement for PV systems on buildings?

• AIt requires that PV system conductors more than a specified distance from the array be re…
• BIt requires the system to shut down automatically at night
• CIt only applies to utility-scale ground-mounted systems
• DIt requires all PV systems to include battery backup

Under the 2017 NEC, what are the rapid shutdown voltage requirements for conductors WITHIN the PV array boundary?

• AThere are no requirements for conductors within the array boundary
• BConductors within the array boundary must be at 0V within 10 seconds
• CConductors within the array boundary must be reduced to 80V or less within 30 seconds of…
• DConductors within the array boundary are exempt from rapid shutdown

Which NEC article specifically covers PV system installation requirements?

• ANEC Article 690
• BNEC Article 480
• CNEC Article 210
• DNEC Article 705 exclusively

An inspector examines a PV system where the inverter has been replaced with a different model than specified in the approved plans. The new inverter has similar specifications. Should the inspector approve the installation?

• ANo, but only if the new inverter has a lower power rating
• BNo, any equipment substitution requires a revised permit application with updated plans a…
• CYes, if the installer provides a verbal explanation for the change
• DYes, if the specifications are similar the substitution is acceptable

What NEC article covers disconnecting means requirements for PV systems?

• ANEC 690.54
• BNEC 690.13
• CNEC 690.7
• DNEC 690.31

A PV system DC disconnect is rated for 600V DC and the maximum system voltage is calculated at 580V DC. Is this acceptable?

• ANo, the disconnect rating must be at least 125% of the maximum system voltage
• BYes, the disconnect voltage rating of 600V DC meets or exceeds the maximum system voltage…
• CNo, the disconnect must be rated for at least 750V DC
• DYes, but only if the system never actually reaches 580V

What type of DC disconnect is commonly used in residential PV systems and what feature must it have?

• AA pull-type fuse holder with no switch mechanism
• BA load-break rated DC disconnect switch that is externally operable, lockable in the open…
• CAny standard light switch rated for AC circuits
• DA knife switch that can be operated under load

For a PV system installed on a building with ungrounded PV source circuits, what additional labeling is required per NEC 690.31(G)(4)?

• ALabels are only required if the system voltage exceeds 300V
• BNo additional labeling is required for ungrounded systems
• CA single label at the main panel is sufficient
• DLabels must indicate 'WARNING: UNGROUNDED PV SYSTEM' and identify the location of all PV…

When inspecting conductor sizing for a PV output circuit with 4 current-carrying conductors in conduit on a rooftop where the ambient temperature above the roof is 65 degrees C, what adjustment factors must be applied?

• ABoth the temperature correction factor for 65 degrees C ambient and the conduit fill adju…
• BOnly the conduit fill adjustment factor
• CNo adjustments are needed for rooftop installations
• DOnly the 125% continuous duty factor

What is the purpose of verifying conductor sizing for a charge controller circuit in an energy storage system?

• ATo verify the conductor length does not exceed 50 feet
• BTo ensure the wire color matches the system design
• CCharge controller circuits do not require conductor sizing verification
• DTo confirm the conductor ampacity is appropriate for the array and charge controller curr…

An inspector examines a charge controller installed in a PV system with a lithium-ion battery bank. What must the inspector confirm about the charge controller?

• AThat the charge controller has WiFi monitoring capability
• BThat the charge controller is suitable for the type of battery storage being used and is…
• CThat the charge controller is made by the same manufacturer as the batteries
• DThat the charge controller is the most expensive model available