Lightning Arrestor (LA)
A lightning arrestor is a rooftop air terminal that intercepts direct lightning strikes and conducts them to a dedicated earth pit, protecting the array and the building. It is standard on commercial plants and tall buildings.
The LA must have its own down-conductor and earth pit, separate from system earthing, and its protective radius should cover the whole array. LA and earth-pit testing is a routine pre-monsoon O&M task.
Frequently Asked Questions
- What is LA in solar?
- LA stands for lightning arrestor — a rooftop air terminal that intercepts direct lightning strikes and routes them to a dedicated earth pit, protecting the array and the building.
- Is a lightning arrestor mandatory for rooftop solar?
- Requirements depend on the building, plant size and DISCOM or tender conditions. It is standard on commercial plants and tall buildings, and good practice wherever lightning risk is significant — ask your installer to document the protection design.
Related Terms
Part of the HUM Solar Glossary — 75+ plain-language definitions for India’s solar ecosystem, maintained as a neutral reference. Browse all terms →
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