Subelement Q: SAFETY— Topic 100: Safety Steps
Question 3-100Q2
Element 3 (GROL)What is the purpose of not putting sharp corners on the ground leads within a building?
Explanation
Lightning, being an extremely high-frequency, high-current transient event, behaves differently than typical AC power. High-frequency currents tend to concentrate on the surface of a conductor (skin effect) and are subject to impedance changes at sharp bends.
Sharp corners in a ground lead create points of high impedance and increased electric field strength. This concentration of charge and increased impedance makes it easier for the lightning current to arc or "jump" across the corner, rather than follow the conductor. This arcing can damage the building structure, create new current paths, or jump to nearby equipment, bypassing the intended ground path. Smooth, gradual bends provide a lower impedance path, allowing the lightning current to flow more effectively and safely to the earth.
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