Course EE-5: Grounding System Design Calculations

1- Course Description:

This course is intended to prepare the target persons with the ability to perform all electrical grounding system design for Domestic, Commercial and Industrial Facilities and AC Substations.




2- The targeted Persons:

Design engineers, new graduate engineers, under graduate engineering students, site field engineers, maintenance engineers and technicians. 

3- Skills Development:

On completion of this course the target person will be able to: 

• Know all the grounding system terminology,

• Distinguish between different types of grounding systems,

• Specify the different components of grounding systems,

• Know design steps for grounding systems,

• Know the required field data for grounding systems design,

• Determine grounding requirements from soil resistivity results,

• Analyze field and tests Data that will be used for grounding systems design,

• Distinguish the different grounding systems included in Domestic, Commercial and Industrial Facilities,

• Performing grounding design calculations by (6) different methods for Domestic, Commercial and Industrial Facilities,

• Know the grounding design procedure for AC Substations,

• Performing grounding design calculations for AC Substations,

• Use the excel spreadsheets for grounding system design for Domestic, Commercial and Industrial Facilities and AC Substations.

4- Course Outline:

1				Introduction to Grounding System Design
2				How Earthing system works
3				Construction of the Earthing System:
	A			Function of Earthing System
	B			Type of Earthing Systems (Part One) (Part Two)
	C			How To Select The Best Earthing System
	D			Earthing System Components (Part One) (Part Two) (Part Three)
	E			Electrical properties of Earthing System
4				Earthing System Design Steps:
	A			First Step: Data Collection (Part One) (Part Two)
	B			Second Step: Data Analysis
	C			Third Step: Grounding Design Calculations:
5				First: for Domestic, Commercial and Industrial Facilities
	A			Grounding system subdivision:
		1		The building exterior grounds
		2		The electrical service grounding
		3		The building interior bonding (Part One) (Part Two) (Part Three)
		4		Equipment grounding and bonding
	B			Ground Design Calculations Methods:
		1		Equation Method
			a	Examples for Equation Method
		2		NomoGraphs Method
		3		Excel Spreadsheet Method
		4		Tables Method:
			a	BS 7671 Requirements for ElectricalInstallations (IEE Wiring Regulations)
			b	NEC, Article 250
		5		Online Earthing Calculators Method:
			a	LPI Eartning Calculator
			b	Loresco Earthing Calculators
			c	Electrician2 Grounding Calculators
		6		Software Programs Method
			a	Erico-GEM Program
6				Second: for AC Substations
	A			Design Procedure Steps:
		1		Step#1: Field Data Collection
		2		Step#2: Earthing Grid Conductor Sizing
		3		Step#3: Calculation Of Tolerable Touch And Step Voltages
		4		Step#4: Preliminary Design Of Grounding System
		5		Step#5: Calculation of of the preliminary Grid Resistance, RG, of the grounding system in uniform soil.
		6		Step#6: Calculation Of Maximum Grid Fault Current, IG
		7		Step#7: Calculation Of Maximum Grid Potential Rise And Comparing With The Tolerable Touch Voltage From Step#3
		8		Step#8: Calculation Of Mesh And Step Voltages
		9		Step#9:Comparing The Computed Mesh Voltage From Step#8 With The Tolerable Touch Voltage From Step#3
		10		Step#10: Comparing The Computed Step Voltage From Step#8 With The Tolerable Step Voltage From Step#3
		11		Step#11: Preliminary Design Modification
		12		Step#12: Detailed Final Design
	B			What is done after finishing the detailed final design of the substation grounding system as a paper work?
	C			Excel Spreadsheets for Grounding System Design Calculations of AC Substation