An Introduction to Electrical Instrumentation & Measurement
Introduction 1.1 Methods of Measurement 4 1.2 Display Methods 16 1.3 Accuracy 22 1.4 Input Characteristics 37 1.5 Waveform 41 1.6 Interference 49 1.7 Selection 51 2. Analogue Instruments 53 2.1 Moving Coil Instruments 53 2.2 The Electrodynamic Instrument 97 2.3 Other Pointer Instruments 103 2.4 Energy Meters 113 2.5 Solid State Indicators 114 2.6 The Cathode Ray Oscilloscope 115 2.7 Instrumentation Tape Recorders 134 3. Comparison Methods 146 3.1 D.C. Potentiometer 146 3.2 A.C. Potentiometer 155 3.3 D.C. Bridges 156 3.4 A.C. Bridges Digital Instruments 186 4.1 Counters 186 4.2 Multi·function Digital Voltmeters 205 4.3 'Intelligent' Instruments 215 4.4 Hybrid Instruments 221 5. Transducers 234 5.l Resistance Change Transducers 238 5.2 Reactance Change Transducers 255 5.3 Semiconductor Devices 261 5.4 Self·generating Transducers 264 5.5 Ultrasonic Transducers 272 5.6 Digital Transducers 272 6. Signal Conditioning 277 6.l Voltage Scaling 277 6.2 Current Scaling 287 6.3 Attenuators 294 6.4 Filters 299 6.5 Probes 308 6.6 Modulation and Sampling 316 6.7 Analogue Processing 319 6.8 Digital-Analogue Conversion 329 7. Interference and Screening 331 7.l Environmental Effects 331 7.2 Component Impurities 334 7.3 Coupled Interference 341 7.4 Noise Rejection Specifications 349 8. Instrument Selection and Specification Analysis 360 8.1 Instrument Selection 360 8.2 Specification Analysis 363 9. Instrumentation Systems 379 9.l System Design 379 9.2 Analogue Systems 380 9.3 Digital Systems Problems and Exercises 10.1 Principles 10.2 Analogue Instruments CONTENTS 10.3 Null or Comparison Measurements 10.4 Digital Instruments 10.5 Transducers 10.6 Signal Conditioning 10.7 Interference 10.8 Selection vii 398 398 400 404 408 410 411 413 415 10.9 Systems 421 10.1 0 Answers 422 Appendix I: Units, Symbols and Conversion Factors 425 Appendix II: Dynamic Behaviour of Moving Coil Systems 430 Appendix III: Equations to Determine the components of a Resistive 'T' Attenuator Pad 437 Index .