Components of a Measurement System
Component
Description
Common Contents
Sensing Element
  • Produces a physical or chemical change in response to variations in the measured parameter (chemical, electrical or physical)
  • Converts a signal into a useful and meaningful value
  • Transducer
Signal Conditioning Element
  • 'Conditions' the signal output of the sensor into a signal suitable for the next stage of operation - mostly through conversion of a physical quantity into an electrical form
  • Some overlap occurs with signal processing
  • Analogue-to-digital convertors (ADC)
  • Resistance circuits (e.g. Wheatstone bridge)
  • Filters
  • Amplifiers
  • Isolators
Signal Processing Element
  • 'Processes' the signal through modification, enhancement and analysis
  • Some overlap occurs with signal conditioning
  • Analogue-to-digital convertors (ADC)
  • Resistance circuits (e.g. Wheatstone bridge)
  • Filters
  • Amplifiers
  • Isolators
Display Presentation Unit
  • Provide an interface between the processed output signal and the clinician
  • Presents graphical or numerical data, often in real-time, with storage and alarm systems
  • Monitor screen
  • Alarm system
  • Data Processor
  • Data Storage