Electrical and Electronics Principles notes KNEC Diploma

Introduction:

Most machines in mechanical engineering use electricity as source of power and use electrical/electronic controls. The understanding of electrical and electronics principles on which they operate is necessary.

The assessment mode shall be mainly practical. Some reference materials for this module unit are listed by the end of the module and it should be noted that this list is not exhaustive.

TOPICS COVERED:

Direct Current Circuits

• State the basic electrical quantities and their units.
• draw electric circuits
• apply electric circuits laws and theorems to solve problems on electrics circuits
• Determine resistance of conductor of a Wheatstone bridge.
• Explain the principle of operation of a potentiometer

Magnetism and Electromagnetism

• Terminologies
• Types of magnets
• Magnetic fields
• Magnetic circuits
• Electromagnetic induction
• Classification of magnetic and non-magnetic materials
• Verification of the existence of magnetic field

Introduction to Direct (D.C.) Generators and Motors

• DC machines
• Separately excited generators
• Shunt wound generators
• Series wound
• Compound wound
• Starting methods
• Voltage regulation
• Speed control
• Maintenance of DC machines

Alternating Current Circuits

• AC circuits
• Wave forms
• Amplitude
• Phase angle
• Period
• Root mean square value
• Average value
• Frequency
• Identification of components of an ac generator
• Sine wave generation
• Experiment of power factor

Battery (chemical cells )

• Types of batteries
• Construction
• Principles of operation

Electron Theory

• Atomic and molecular structure
• Semiconductor materials
• Intrinsic and extrinsic conduction
• Crystal structure of semiconductor
• Crystal structure of semiconductor
• Formation of P- and N-type semiconductor

Semiconductor Devices

• Construction and symbol of semiconductor devices
• Operation of semi conductor devices
• Characteristics of semi-conductor devices
• Applications of semiconductor devices
• Identification of semi conductor devices
• Connection of semiconductor devices
• Tests on semiconductor components

Electronic Components

• Electronics Components

Power Rectification

• Methods of power rectification
• Smoothing
• Regulation
• Voltage multipliers
• Methods of power Supply protection
• Voltage division and multiplication
• Construction of power supply regulators
• Tests and measurements