Proper grounding of a photovoltaic (PV) power system is critical to helping ensure electrical safety during its lifetime. PV equipment needs to be properly bonded, in addition to code-compliant grounding, so that the low current flows on metal parts can facilitate the operation of over current and ground-fault protection devices.
The standard UL 2703 covers mounting systems, including mounting devices, clamping devices and ground lugs for use with photovoltaic modules and panels and contains requirements for ground-mounted and roof systems as part of a nonstructural building component.
In addition, UL 2703 is used to determine the fire classification of a rooftop-mounted PV system (which includes both a specific PV module and the racking system) as required for compliance with the building code requirements, which is to maintain the fire performance integrity of the roof. It is looking at the overall installation resistance to external fire exposure.
Further, while UL 3703 for Solar Tracker involves rigorous inspection and evaluation of a tracker platform it also references UL2703 for electrical requirements related to the mounting, bonding and grounding system.