Electrical and electronic components, devices, and systems

Electrical and electronic components, devices, and systems

Basics of Electricity

  • Electricity is a form of energy resulting from the existence of charged particles like electrons and protons, either static or moving.
  • Current (I) is the amount of charge passing through a specific point in a circuit per second. It is measured in Amperes (A).
  • Voltage (V) is the electrical force that drives the current around the circuit. It is measured in Volts (V).
  • Resistance (R) is opposition to the flow of current and is measured in Ohms (Ω).
  • The relationship between these three factors is given by Ohm’s Law, which states that V=IR.

Electrical and Electronic Components

  • Resistors limit the flow of current in a circuit. The higher the resistance, the less current flows for a given voltage.
  • Capacitors store electric charge. They are used in filtering, tuning circuits and time-delays.
  • Inductors store energy in their magnetic field and are commonly used in tuned circuits and for power supply smoothing.
  • Diodes allow current to flow in one direction only.
  • Transistors are devices that can amplify an electrical signal or act as an electronic switch.
  • Integrated Circuits (ICs) contain many transistors, resistors, diodes and other components, offering complex functions in a small package.

Devices and Systems

  • Power Supplies convert electricity from one form to another - often from AC to DC.
  • Oscillators generate a repetitive signal, usually a sine wave or square wave.
  • Amplifiers increase the magnitude of a signal.
  • Filters remove or enhance frequencies in electronic signals.
  • Logic gates are fundamental building blocks of digital circuits.

Circuits and Systems

  • Series circuit: Components are connected end-to-end so the same current flows through each one.
  • Parallel circuit: Each component is separately connected to the power source, so the voltage is the same across each one.
  • Complex (Mixed) circuit contains combinations of series and parallel connections.
  • Digital Systems: Utilise digital signals that represent binary numbers, zeros and ones.
  • Analogue systems: Utilise signals that are a continuous waveform.
  • A Transducer converts one form of energy to another - for example, a microphone converts sound waves into electrical signals.
  • Relays and Contactors are electrically controlled switches used for controlling large power loads.

Safety Measures

  • Understand the Hazard and Risk Assessment.
  • Use of Personal Protective Equipment (PPE) for safety.
  • Awareness of Electrical Isolation to avoid electric shock.
  • Knowledge of Emergency Procedures in case of any unfortunate incident.