Lightning protection/bonding: how should UL 96A lightning systems interface with Solar Roof conductors and metal flashings without compromising PVRSE or creating step-potential risks?
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Bond all exposed metal (solar racking, flashings, etc.) to the lightning protection ground to ensure safety and reduce step-potential risks.
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Do not connect lightning system directly to solar panel conductors or DC wiring—it can interfere with PV system isolation and rapid shutdown (NEC 690.12).
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Maintain 6+ feet separation between lightning down conductors and PV system wiring to reduce induced surges.
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Install UL-listed surge protection devices (SPDs) at inverter, combiner, and main panel to protect solar equipment.
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Follow solar manufacturer guidelines (e.g., Tesla Solar Roof) for proper grounding points.
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Integrating UL 96A-compliant lightning protection systems with solar roof conductors and metal flashing requires careful attention to bonding, material compatibility, and adherence to both roofing and lightning protection standards.
- Bonding and Equalization
All conductive components, including solar panel frames, mounting systems, and metal flashings, should be bonded to the lightning protection system. This ensures equal electrical potential across components, minimizing the risk of side flashes during lightning events.
-Material Compatibility
Avoid direct contact between dissimilar metals to prevent galvanic corrosion. For instance, do not install copper lightning protection components on aluminum roofing materials. Use compatible materials or appropriate isolation techniques to mitigate corrosion risks.
- Installation Practices
Lightning protection components should be installed in accordance with both the roof covering manufacturer’s instructions and relevant codes. For membrane roofs, secure air terminals and conductors using adhesives compatible with the roofing material or by attaching them to nonporous blocks as prescribed.
-Compliance with Building Codes The 2024 International Building Code (IBC) specifies that lightning protection system components attached to metal edge systems or gutters must be installed using compatible brackets, fasteners, or adhesives, following the manufacturer’s instructions. If the manufacturer’s guidelines are unavailable, a registered design professional should provide direction.
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Okay, so when you’re putting lightning protection on a Solar Roof, make sure all metal stuff is hooked up to each other and the building’s ground. That way, if lightning hits, everything stays at the same electrical level. Just a heads up: don’t hook up the lightning wires straight to the solar panel wires, since that can mess up the whole system. Keep those lightning cables away from the PV wires and stick to the right spacing. And hey, if you’re using Tesla’s stuff, always double-check with them or your installer before you change anything. It’s all about keeping things safe and not messing up your warranty. Getting the grounding and spacing right helps keep your house and solar stuff safe when lightning strikes.