Tài liệu Electrical grounding techniques from LEM

Electrical grounding techniques from LEM (20 pages)

Ground Resistance - Principles, Testing, Techniques & Applications
Table of Contents


Why Ground ? 1
What is a ground and what does it do ? 1
Ground Resistance Values .1
Ground Electrodes 2
Types of Ground Systems 4
Ground Resistance Testing - Soil Resistivity .4
Measuring Soil Resistivity 4 - Pole Method 5
Ground Resisting Testing 3 - Pole Fall of Potential 7
Ground Resistance Testing Existing Systems Selective Clamp - On 8
Ground Resistance Testing Existing Systems Stakeless 10
Ground Resistance Testing 2 - Pole 10
Ground Impedance Measurements 11
Measuring Ground Resistance at Substations 11
Measuring Ground Resistance at Central Offices .12
Measuring Ground Resistance at Cellular Sites/Microwave and Radio Towers . 13
Measuring Ground Resistance at Remote Switching Sights 14
Measuring Ground Resistance for Lightning Protection Commercial/Industrial 15
Ground Testing Instruments - UNILAP GEO / GEO X 16
Ground Testing Instruments - SATURN GEO / Handy GEO .17




There are a number of good reasons to ground but primary among them is to ensure personnel safety. The following agencies and organizations all have recommendations and / or standards for grounding, to ensure that personnel safety is being protected. The organizations that provide guidelines/rules for grounding are: The International .