Measurements & Instrumentation

What you'll learn

• Describe a measurement system as sensing, conditioning and output stages, use the vocabulary of metrology correctly, and explain calibration, as-found and as-left results, and traceability to national standards through accredited laboratories.
• Summarize repeated measurements with means, standard deviations and Student t confidence intervals, test suspect readings with Grubbs' test and Chauvenet's criterion, and fit and judge calibration lines.
• Evaluate measurement uncertainty by the GUM method, with Type A and Type B evaluations, sensitivity coefficients, combined and expanded uncertainty and Monte Carlo propagation, and build an uncertainty budget.
• Interpret the static characteristics of instruments and predict the dynamic response of first- and second-order sensors, including the effect of installation on natural frequency.
• Design signal conditioning with bridges, instrumentation amplifiers and filters, and prevent interference through separation, twisting, shielding, differential inputs and correct grounding without compromising safety grounds.
• Choose sampling rates, anti-aliasing filters and converter resolution, account for multiplexing, and design and check 4 to 20 mA current loops.
• Explain strain gauges, torque transducers and load cells, choose transducer ranges for a working point, and cross-check torque by an independent method.
• Measure pressure with suitable references and sensors, calibrate with a deadweight tester corrected for local gravity, and calculate pump total head correctly from installed transducers.
• Measure temperature with RTDs, thermocouples, thermistors and infrared thermometers, choose connections and compensation, and estimate installation errors.
• Select and install flowmeters of different principles, and calibrate a flowmeter gravimetrically with appropriate corrections.
• Measure speed, position, shaft motion and vibration with suitable sensors, and choose counting methods and accelerometer mountings for the frequencies of interest.
• Plan tests and experiments with replication, randomization, blocking and factorial designs, reduce pump test data to rated speed, and judge conformity to a guarantee using measurement uncertainty and a decision rule.