About This Manual Conventions .xi Related Documentation xii Chapter 1 Overview of Measurement and Virtual Instrumentation Virtual Instrumentation 1-1 System Components for Taking Measurements with Virtual Instruments 1-2 Chapter 2 Comparing DAQ Devices and Computer-Based Instruments for Data Acquisition General-Purpose DAQ .2-1 How Computers Talk to DAQ Devices .2-2 Role of Software 2-3 NI-DAQ .2-3 Instrument I/O 2-4 How Computers Control Instruments 2-4 Instrument Drivers .2-4 Chapter 3 Configuring Measurement Hardware Installing and Configuring Hardware 3-1 Configuring Hardware on Windows 3-2 Measurement & Automation Explorer 3-2 DAQ Assistant .3-3 Configuring VISA Devices and IVI Logical Names .3-3 Configuring FieldPoint Modules .3-3 Configuring Hardware on Mac OS 3-3 NI-DAQ Configuration Utility 3-4 NI-488.2 Configuration Utility 3-4 Configuring Serial Ports on Macintosh .3-4 Chapter 4 Measurement Fundamentals Signal Acquisition . 4-1 Signal Sources . 4-2 Grounded Signal Sources 4-2 Floating Signal Sources 4-3 Signal Conditioning . 4-3 Amplification 4-4 Linearization . 4-5 Transducer Excitation . 4-6 Isolation . 4-6 Measurement Systems . 4-6 Differential Measurement Systems . 4-6 Common Mode . 4-7 Referenced and Non-Referenced Single-Ended Measurement Systems 4-9 Summary of Signal Sources and Measurement Systems 4-10 Hardware versus Software Timing 4-12 Sampling Rate . 4-12 Aliasing . 4-12 Determining How Fast to Sample . 4-14 Digital I/O 4-15 Digital Lines and Ports 4-16 Handshaking 4-16 Triggering 4-17 Analog Edge Triggering 4-17 Analog Window Triggering 4-18 Digital Edge Triggering 4-19 Signal Analysis 4-20 Filtering . 4-20 Windowing 4-20 Spectral Leakage . 4-20 Device Calibration . 4-22 External Calibration 4-22 Internal Calibration . 4-22 Chapter 5 Creating a Typical Measurement Application I/O Controls . 5-1 Traditional DAQ Channel Control 5-1 DAQmx Name Controls 5-2 IVI Logical Name Control 5-2 VISA Resource Name Control 5-2 FieldPoint I/O Point Control .5-2 Motion Resource Name Control 5-2 Polymorphic VIs 5-3 Properties .5-3 Creating a Typical DAQ Application 5-4 Physical and Virtual Channels .5-5 Tasks 5-5 Waveform Control and Digital Waveform Control .5-6 Start Time (t0) .5-6 Delta t (dt) .5-6 Waveform Data and Digital Waveform Data (Y) .5-6 Attributes .5-7 Displaying Waveforms .5-7 Using the Waveform Control 5-8 Using the Digital Waveform Control 5-11 Creating a Typical VISA Application .5-11 Creating a Typical FieldPoint Application 5-11 Channels versus Items .5-11 Using the FieldPoint I/O Point Control .5-11 Chapter 6 Measuring DC Voltage Overview of DC Measurements 6-1 Using NI-DAQ VIs to Measure DC Voltage .6-1 Traditional NI-DAQ Method .6-2 NI-DAQmx Method 6-3 Averaging a Scan .6-3 Traditional NI-DAQ Method 6-4 NI-DAQmx Method 6-5 Measuring DC Voltage with Instruments 6-6 Chapter 7 Measuring AC Voltage Overview of AC Measurements 7-1 Measuring AC Voltage with Instruments 7-1 Traditional NI-DAQ Method .7-2 NI-DAQmx Method 7-2 Measuring Maximum, Minimum, and Peak-to-Peak Voltage with Instruments .7-3 Using Instruments to Measure AC Voltage .7-4 Using an Instrument to Measure Peak-to-Peak Voltage 7-5 Using FieldPoint VIs to Measure AC Voltage 7-6 Chapter 8 Measuring Temperature Using NI-DAQ VIs to Measure Temperature . 8-1 Traditional NI-DAQ Method 8-2 NI-DAQmx Method 8-2 Using FieldPoint VIs to Measure Temperature . 8-3 Chapter 9 Measuring Current Overview of Current Measurements . 9-1 Using NI-DAQ VIs to Measure Current . 9-3 Traditional NI-DAQ Method 9-3 Measuring Current with Instruments . 9-4 Using FieldPoint VIs to Measure Current . 9-5 Chapter 10 Measuring Strain Overview of Strain Measurements 10-1 Using NI-DAQmx VIs to Measure Strain . 10-3 Using FieldPoint VIs to Measure Strain 10-3 Chapter 11 Measuring Resistance Overview of Resistance Measurements . 11-1 2-Wire Resistance . 11-1 4-Wire Resistance . 11-3 Using DMMs to Measure Resistance 11-4 Chapter 12 Generating Voltage Overview of Generating Voltage . 12-1 Single-Point Analog Output 12-1 Buffered Analog Output 12-1 Connecting Analog Output Signals . 12-2 Using Traditional NI-DAQ VIs for Single-Point Updates 12-2 Immediate Updates . 12-3 Multiple Immediate Updates . 12-3 Using Traditional NI-DAQ VIs for Waveform Generation . 12-4 Single-Buffered Analog Output 12-4 Circular-Buffered Analog Output . 12-5 Using NI-DAQmx VIs to Generate Voltage 12-6 Generating Voltage with Instruments 12-7 Chapter 13 Measuring Analog Frequency Using NI-DAQ VIs to Measure Analog Frequency 13-1 Traditional NI-DAQ Method .13-1 NI-DAQmx Method 13-2 Measuring Frequency Using Instruments 13-3 Measuring Frequency with Filtering 13-3 Chapter 14 Measuring Digital Pulse Width, Period, and Frequency Overview of Counters 14-1 Counter Parts .14-2 Overview of Time Measurements 14-2 Quantization Error .14-3 Quantization Error with Counter Time Measurements .14-4 Two Counter Measurement Method 14-5 High-Frequency Two Counter Measurement Method 14-5 Quantization Error with High-Frequency Two Counter Measurement Method 14-6 High-Frequency Two Counter Measurement Method Using NI-DAQmx 14-7 Large-Range Two Counter Measurement Method 14-8 Quantization Error with Large-Range Two Counter Measurement Method 14-9 Chapter 15 Generating Digital Pulses Overview of Generating a Digital Pulse 15-1 Using NI-DAQmx VIs to Generate a Digital Pulse .15-5 Using FieldPoint VIs to Generate a Digital Pulse .15-5 Chapter 16 Using LabVIEW to Control Instruments Overview of Instrument Drivers 16-1 Installing Instrument Drivers .16-2 Instrument Driver Directory 16-2 Organization of Instrument Drivers .16-3 Types of Instrument Drivers . 16-4 LabVIEW Plug and Play Drivers . 16-5 IVI Drivers 16-5 Contributed Instrument Drivers 16-5 VISA in LabVIEW 16-6 Message-Based Communication versus Register-Based Communication . 16-6 Verifying Communication with an Instrument 16-7 Instrument I/O Assistant . 16-7 Verifying VISA Communication 16-8 Getting Started VI . 16-8 Customizing the Getting Started VI for Measurements . 16-8 Common Instrument Driver VIs Inputs and Outputs 16-9 Resource Name/Instrument Descriptor . 16-9 Error In/Error Out Clusters . 16-9 Writing VISA Applications . 16-9 Using VISA Properties 16-10 Using VISA Events . 16-11 Handling GPIB SRQ Events Example . 16-11 Using Advanced VISA VIs . 16-11 Data and String Manipulation Techniques 16-11 Using Instrument I/O Assistant for Data Manipulation 16-12 Formatting Commands into Strings 16-12 Formatting Data Retrieved from an Instrument 16-13 Waveform Transfers . 16-14 Appendix A Types of Instruments Appendix B Technical Support and Professional Services Glossary Index LVMeasurementManual
