The generalized measurement system

Compare to Figure 2.1 Measurand Sensing element Signal modification subsystem Indicator or recorder

The system--what we want to know about

The probe--experiences a physical change Does the probe perturb the system?

The transducer--produces a voltage signal

The signal conditioner--changes the voltage Amplify Attenuate Filter

The A/D converter--produces binary numbers

Analysis and display--numbers, graphs, etc.

Base SI units DimensionSI unit masskilogram (kg) lengthmeter (m) timesecond (s) temperatureKelvin (K) electric currentampere (A) chargeCoulomb (C) 1 A = 1 C/s

Other SI units DimensionSI unit velocitymeter per second (m/s) forceNewton (kg-m/s 2 ) voltageVolt (V) resistanceOhm (  )

SI unit multipliers M (‘mega”)1,000,000 k (“kilo”) 1,000 c (“centi”) 1/100 m (“milli”) 1/1,000  (“micro”) 1/1,000,000

Some common British units DimensionSI unit lengthinches (in or “), feet (ft or ‘) masspound mass (lbm) forcepound (lb)