EARTHING HEALTH ASSESSMENT
GLOBAL EARTHING SOLUTIONS Health Assessment ensures the healthiness of the complete Earthing system. The earthing system must be inspected periodically to ensure health and effectiveness. Since the majority of Earthing System is buried underground/inaccessible, it suffers from “OUT OF SIGHT IS OUT OF MIND” syndrome. Unseen Components like Equipment Earth Conductor (Strip), Earth Grids / Mats which are buried or inaccessible, tend to be taken for granted or ignored, though they are crucial.
As per CEA regulation 41 (xv) b, the resistance of earthing system shall be maintained as low as possible such that sufficiently large fault current flows in the circuit and the breaker trips ON TIME to isolate the faulty circuit.
A Complete Earthing System with all its components- Equipment Earth Conductor, Earth Electrode, and Earth Grid / Mat should offer a low resistance path for fault current to flow so that breakers trip on time to prevent accidents such as -Fire, Short Circuit, and Electric Shock and so on.
Why Earthing Health Assessment Audit?
Earthing Health Assessment Audit is needed because earthing deteriorates over time due to various reasons such as Chemical Properties of Soil leading to Environmental Corrosion, Thermal & Electrical Stress on joints due to Electrical Faults, Galvanic Corrosion in some cases and Improper Workmanship.
Normally Earth Electrode (Pit) Resistance alone is measured periodically. Electrical System is deemed safe with a low Earth Electrode Resistance.
The Integrity of the Earth Conductor (Strip) between the Earth Electrode and Equipment is rarely checked. Hence, Breaker may not trip even if Earth Electrode Resistance is low.
In reality, timely operation of the breaker (Electrical Safety) depends on the resistance of earth loop formed by equipment the earth conductor (Strip), earth electrode and phase conductor.
System modifications and Deterioration of Earthing system can render the original design calculations of protection systems (breakers) invalid.
GES’s assessment methodology covers this crucial gap by checking all the above parameters, thereby ensuring timely operation of the breakers to prevent accidents/damage.
Carried out on live systems without shut down using sophisticated meters and practices. By emphasizing and encouraging the use of the right personal protection equipment.
Design risk mitigation/ management measures to enhance safety.
Earthing Health Assessment Audit Overview
Application Area: AIS & GIS Substations, Commercial Buildings, Retails outlets, Warehouses, Data Center's, Factories, Manufacturing Plants, Oil & Gas, Metro rail, Process plants, Wind & Solar Plants, Tank farms, Critical structures like communication towers, power plants and more.
Reference Standards: IEEE 81-2012 | IEE Regulation | CEA regulations for measures relating to safety and electric supply - 2021 (Draft) | IEEE 80 – 2013 | IS 3043 | BS 7430 | CBIP manual-339
Why Earthing Health Assessment Audit?
Earthing Health Assessment Audit is needed because earthing deteriorates over time due to various reasons such as Chemical Properties of Soil leading to Environmental Corrosion, Thermal & Electrical Stress on joints due to Electrical Faults, Galvanic Corrosion in some cases and Improper Workmanship.
Normally Earth Electrode (Pit) Resistance alone is measured periodically. Electrical System is deemed safe with a low Earth Electrode Resistance.
The Integrity of the Earth Conductor (Strip) between the Earth Electrode and Equipment is rarely checked. Hence, Breaker may not trip even if Earth Electrode Resistance is low.
In reality, timely operation of the breaker (Electrical Safety) depends on the resistance of earth loop formed by equipment the earth conductor (Strip), earth electrode and phase conductor.
System modifications and Deterioration of Earthing system can render the original design calculations of protection systems (breakers) invalid.
GES's assessment methodology covers this crucial gap by checking all the above parameters, thereby ensuring timely operation of the breakers to prevent accidents/damage.
Carried out on live systems without shut down using sophisticated meters and practices. By emphasizing and encouraging the use of the right personal protection equipment.
Design risk mitigation/ management measures to enhance safety
EHV EARTHING AUDITS
ACTIVITY
• Soil Resistivity Test.
• Earth Electrode Resistance Test.
• Riser Integrity Test.
• Grid Integrity Test.
• Effect of Corrosion.
• Touch and Step Potential Test.
• Modelling and Simulation of earth grids for safe touch & step potentials.
LV EARTHING AUDITS
ACTIVITY
• Soil Resistivity Test.
• Earth Electrode Resistance Test.
• Earth Loop Impedance Test.
• Prospective Fault Current Test.
• Riser Integrity Test.
• Effect of Corrosion
BENIFITS :
• Reduction in equipment failures by about 38-40%.
• Enhanced reliability of equipment.
• Reduces nuisance tripping.
• Improves human safety.