NABCEP - Certified North American Board of Certified Energy Practitioners Specialist NEC Article 690 Applications Questions and Answers

Question 1

According to NEC Article 690, which of the following is a primary requirement for the location of a PV system disconnecting means?

Accepted Answer

It must be installed in a readily accessible location.

Answer

It must be within sight of the PV array.

Answer

It must be located on the roof within 6 feet of the array.

Answer

It must be located exclusively inside the building near the main service panel.

Question 2

A rooftop PV system is being installed on a single-family dwelling. Per NEC 690.12, what are the voltage and time limitations for controlled conductors *inside* the array boundary after rapid shutdown is initiated?

Accepted Answer

80 volts within 30 seconds

Answer

30 volts within 10 seconds

Answer

120 volts within 60 seconds

Answer

30 volts within 30 seconds

Question 3

When calculating the required ampacity for PV source circuit conductors, what multiplier is applied to the module's short-circuit current (Isc)?

Accepted Answer

125%

Answer

100%

Answer

110%

Answer

156%

Question 4

Which of the following is required by NEC Article 690 regarding the grounding of a grid-tied PV system installed on a building?

Accepted Answer

Exposed non-current-carrying metal parts, like module frames and racking, must be bonded and connected to an equipment grounding conductor.

Answer

A separate grounding electrode must always be installed at the array location.

Answer

Only the DC equipment needs to be grounded; the AC side is covered by the main service.

Answer

Functional grounding is prohibited for all PV systems.

Question 5

An installer is running PV source circuits from a rooftop array through the attic to a string inverter in the garage. According to NEC 690.31, which wiring method is typically required once the conductors penetrate the building?

Accepted Answer

The conductors must be installed in a metallic raceway or be a Type MC cable.

Answer

Direct-burial rated USE-2 cable can be run without conduit inside the building.

Answer

The conductors can be run without a raceway as long as they are secured every 4.5 feet.

Answer

Any listed cable suitable for wet locations is acceptable.

Question 6

For a PV system operating at 96V DC on the roof of a commercial building, what specific type of protection is required by NEC 690.11 to mitigate fire hazards?

Accepted Answer

DC arc-fault circuit protection (AFCI)

Answer

Ground-fault circuit-interrupter (GFCI) protection

Answer

Surge protective device (SPD)

Answer

Reverse-current protection