NABCEP PV System Mechanical Installation 5

Question 1

Which UL standard specifically covers mounting systems (racks and rails) for PV modules?

Accepted Answer

UL 2703

Answer

UL 2703 covers rack mounting systems for flat-plate photovoltaic modules and panels, including bonding and grounding requirements.

Question 2

A roof-mounted PV system has rails running parallel to the roof slope (portrait landscape). This rail orientation is called:

Accepted Answer

Parallel (portrait) rail configuration

Answer

When rails run parallel to the roof slope with modules in portrait orientation, this is called a parallel or portrait rail configuration.

Question 3

What is the maximum recommended unsupported span for a standard aluminum extrusion rail in most residential PV racking systems?

Accepted Answer

48 inches

Answer

Most residential aluminum rails are rated for spans up to approximately 48 inches between attachment points without exceeding deflection limits.

Question 4

When installing a PV system on a flat roof with a membrane (TPO/EPDM), what is the primary advantage of a non-penetrating ballasted system?

Accepted Answer

Preservation of the roof warranty by avoiding penetrations

Answer

Ballasted systems avoid puncturing the membrane, which would void most roofing warranties and create potential leak points.

Question 5

What is the primary mechanical hazard when installing PV modules on a steep-slope roof (>8:12 pitch) without proper fall protection?

Accepted Answer

Installer falling from the roof

Answer

Steep roofs dramatically increase the risk of a worker fall, which is the leading cause of fatality in roofing work; OSHA requires fall protection at 6 feet.

(NABCEP) Certified North American Board of Certified Energy Practitioners Specialist Practice Test

(NABCEP) Certified North American Board of Certified Energy Practitioners Specialist Practice Test

NABCEP PV System Mechanical Installation 5