The ground clearance is the distance between ground level and bottom of any insulator in an outdoor substation. 5 meters for all voltage levels. It prevents electrical arcing and breakdown between these parts. It requires consideration of voltage levels, environmental conditions, and manufacturing processes, adherence to relevant standards, and optimization through simulation. If the switchgear or bus section can be taken out of service and grounded as a unit, then the clearance between its individual phases is an engineering decision*. The clearances between the components being worked on and the adjacent equipment, which may still be energized, should be addreesd by. Creepage (Leakage distance) is the shortest path between two conductive parts (or between a conductive part and the bounding surface of the equipment) measured along the surface of the insulation.
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