Earth pipes (grounding electrodes) are critical components of substation earthing systems, providing a low-resistance path for fault currents.

Types of Earth Electrodes

• •Pipe electrodes: GI or copper pipes driven into soil
• •Rod electrodes: Solid copper-bonded steel rods
• •Plate electrodes: Buried metal plates
• •Strip electrodes: Horizontal conductors in trenches

Installation Guidelines

• •Depth: Minimum 2-3 meters for pipe electrodes
• •Soil treatment: Bentonite or charcoal for low resistivity
• •Connections: Exothermic welding or compression fittings
• •Protection: Concrete chamber at surface level

Testing Requirements

• •Initial resistance measurement
• •Periodic testing (annually)
• •Documentation of readings
• •Comparison with design values