EE-4: Basic Electrical design course – Level III

Course Description:

This third level design course is intended to prepare the target persons with the ability to perform the following electrical design calculations:

1. Over current Protection Calculations,
2. Conductor Ampacity Calculation,
3. Voltage Drop Calculations.

The targeted Persons:

Design engineers, New graduate engineers, under graduate engineering students.




Skills Development:


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

• Design the overcurrent protection devices OCPD,

• Select the proper overcurrent protection for certain applications,

• Locating of the overcurrent protection devices OCPDs,

• Perform Conductor Ampacity Calculation,

• Perform Voltage Drop Calculations,

• Create excellent knowledge base for advanced Level of electrical design course.

Course Outline:

First: Over current Protection Calculations:

1- Over Current Protection Definitions



2- Sizing of Overcurrent Protection Devices (OCPDs)



3- How to select the proper overcurrent protection for certain applications:

A- Conductors,

B- Flexible Cords and Flexible Cables,

C- Fixture Wires.



4- Selecting the proper overcurrent protection devices (OCPDs) for certain application


5- Locating of the overcurrent protection devices OCPDs - Part One

6- Locating of the overcurrent protection devices OCPDs - Part Two

Second: Conductor Ampacity Calculations:

1- Conductors and Cables Terms Definitions


2- Measurement Units of Conductors Cross Section Area


3- Conversions between different Measurement Units of Conductors Cross Section Area


4- Standard Sizes of Conductors


5- Methods for Ampacity Calculations of Conductors Rated 0–2000 Volts


First Method: Conductor Ampacity Calculations from Tables as provided in 310.15(B)

A- General Overview of Allowable Ampacity Tables for conductors rated 0 to 2000 volts


B- Rules controlling the conductor ampacity calculations


C- Correction Factors Affecting Conductor Ampacity Tables


D- Special Cases for Conductor Ampacity Calculations


E- Conductors and Cables Ampacity Calculations in Cable Trays



Second Method: Conductor Ampacity Calculation Under engineering supervision, as provided in 310.15-C


A- Using Annex B Tables (Part One)

B- Using Annex B Tables (Part Two)

C- Using Annex B Tables (Part Three)

D- Using Annex B Tables ((Part Four)

E- Using Annex B Tables (Part Five)


6- Conductor Sizing and Overcurrent Protection Calculations for Continuous and Non-Continuous Loads

Third: Voltage Drop Calculations:

Methods of Voltage Drop Calculations:

1- Ohm’s Law Method


2- European Method



3- U.S Method

A- Circular-mils method

B- Chapter (9) tables method - Part One

C- Chapter (9) tables method - Part Two



4- Approximate Mathematical Method



5- Ampere-Feet Method



6- Lookup Tables Method



7- Quick On-Line Method



8- Excel Spreadsheets Method