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TM TM
LabVIEW SignalExpress
Getting Started with LabVIEW SignalExpress
Getting Started with LabVIEW SignalExpress
August 2007
373873C-01
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Support Worldwide Technical Support and Product Information ni.com National Instruments Corporate Headquarters 11500 North Mopac Expressway Austin, Texas 78759-3504 USA Tel: 512 683 0100 Worldwide Offices Australia 1800 300 800, Austria 43 662 457990-0, Belgium 32 (0) 2 757 0020, Brazil 55 11 3262 3599, Canada 800 433 3488, China 86 21 5050 9800, Czech Republic 420 224 235 774, Denmark 45 45 76 26 00, Finland 385 (0) 9 725 72511, France 01 57 66 24 24, Germany 49 89 7413130, India 91 80 411900
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Important Information Warranty The media on which you receive National Instruments software are warranted not to fail to execute programming instructions, due to defects in materials and workmanship, for a period of 90 days from date of shipment, as evidenced by receipts or other documentation. National Instruments will, at its option, repair or replace software media that do not execute programming instructions if National Instruments receives notice of such defects during the warranty perio
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THE SUITABILITY OF NATIONAL INSTRUMENTS PRODUCTS WHENEVER NATIONAL INSTRUMENTS PRODUCTS ARE INCORPORATED IN A SYSTEM OR APPLICATION, INCLUDING, WITHOUT LIMITATION, THE APPROPRIATE DESIGN, PROCESS AND SAFETY LEVEL OF SUCH SYSTEM OR APPLICATION.
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Contents About This Manual Conventions ...................................................................................................................vii Related Documentation..................................................................................................vii Chapter 1 Introduction to LabVIEW SignalExpress Chapter 2 Installing LabVIEW SignalExpress LabVIEW SignalExpress LE .........................................................................................2-1 Minimum Sy
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Contents Chapter 5 Logging Data Recording a Signal ........................................................................................................ 5-1 Viewing a Logged Signal .............................................................................................. 5-2 Logging Signals with Predefined Start and Stop Conditions ........................................ 5-3 Analyzing Logged Signals .........................................................................................
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About This Manual Use this manual to familiarize yourself with LabVIEW SignalExpress interactive measurements and the basic LabVIEW SignalExpress features that you use to acquire and analyze signals. This manual contains exercises that help you begin working with LabVIEW SignalExpress. These exercises teach you how to run projects, configure steps, work with signals, configure sweep measurements, log data, and extend LabVIEW SignalExpress with LabVIEW graphical programming. Conventions The
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1 Introduction to LabVIEW SignalExpress National Instruments provides innovative solutions for scientists and engineers to build automated measurement systems based on industry-standard computers and platforms. National Instruments develops robust, industry-leading programming environments for automating measurement systems, such as LabVIEW for graphical development, ™ ™ LabWindows /CVI for ANSI C programming, and Measurement Studio for Microsoft Visual Studio programming. You can use the
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2 Installing LabVIEW SignalExpress You can use the LabVIEW SignalExpress CD to install LabVIEW SignalExpress and complete the exercises in this manual. LabVIEW SignalExpress LE LabVIEW SignalExpress LE gives you a 30-day trial of the Full version of LabVIEW SignalExpress. After that period, you must activate your version of LabVIEW SignalExpress LE or purchase the Full version. If you activate your version of LabVIEW SignalExpress LE before your 30-day trial of the full version is complete
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Chapter 2 Installing LabVIEW SignalExpress Installing LabVIEW SignalExpress Complete the following steps to install LabVIEW SignalExpress on Windows Vista/XP/2000/NT. Note If you want to convert LabVIEW SignalExpress projects to LabVIEW block diagrams, you must install LabVIEW 7.1 or later before you install LabVIEW SignalExpress. 1. Disable any automatic virus detection programs before you install. Some virus detection programs interfere with the installation program. 2. Log on as an admini
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3 Working with Projects You can use LabVIEW SignalExpress to define measurement procedures by adding and configuring steps in an interactive measurement environment. A step is a configurable function that acquires, generates, analyzes, loads, or stores signals. Most steps process input signals and produce output signals. You can configure the operation of a step by specifying values in a configuration view. A saved sequence of configured steps is a LabVIEW SignalExpress project. This chapt
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Chapter 3 Working with Projects 1 9 2 3 4 5 6 5 8 7 1 Execution control buttons 4 Input 7 Logged Data window 2 Work Area pull-down menu 5 Output 8 Data View 3Step 6Project View 9 Record button Figure 3-1. First Project.seproj The left pane is the Project View, which presents the order of operations, or steps, for the project. The right pane is the Data View, which displays the signal that the project generates and analyzes. Running a Project and Displaying Signals LabVIEW SignalExpress has tw
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Chapter 3 Working with Projects results immediately. If you modify the configuration of steps while a project runs, LabVIEW SignalExpress gives you direct, immediate feedback on the changes you make. When you click the Run Once button, LabVIEW SignalExpress executes all steps in the project one time. Complete the following steps to run the sample project and display signals. 1. Click the Run button, shown at left, to execute all steps in the project continuously. The project loads a signal f
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Chapter 3 Working with Projects 5. Drag the rms output to the table to display the scalar RMS measurement. LabVIEW SignalExpress creates a new row in the table to display the second measurement. The project should appear as shown in Figure 3-2. Figure 3-2. Outputs of First Project.seproj Configuring a Step A step is a configurable function that acquires, generates, analyzes, loads, or stores signals. Steps process input signals and produce output signals. You can configure the operation of
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Chapter 3 Working with Projects Complete the following steps to configure the Distortion step and the Amplitude and Levels step. 1. Double-click the Distortion step in the Project View. The Step Setup dialog box for the Distortion step appears, as shown in Figure 3-3. Figure 3-3. Distortion Step Setup Dialog Box On the Configuration tab, the settings indicate that the Distortion step receives a time-domain waveform signal as an input, performs a power spectrum on the signal to convert it to
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Chapter 3 Working with Projects 3. On the Configuration tab, select Fundamental Tone from the Export signals (THD) pull-down menu. The operation of the step changes from displaying the frequency-domain spectrum of the entire input signal to displaying only the frequency spectrum of the fundamental tone of the input signal. The graphed signals in the top half of the Step Setup dialog box update to reflect the change you made. 4. Select Harmonics Only from the Export signals (THD) pull-down
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Chapter 3 Working with Projects 6. Click the Input/Output tab to display the list of possible inputs and outputs for this step, as shown in Figure 3-4. Figure 3-4. Amplitude and Levels Step Setup Dialog Box 7. Place checkmarks in the Export +peak value, Export -peak value, and Export peak-peak value checkboxes to configure the Amplitude and Levels step to return three additional measurements. Three additional outputs appear in the Project View. 8. Click the Data View tab to display the Data
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Chapter 3 Working with Projects 11. Select File»Save Project As and save the project as My First Project.seproj in the SignalExpress\Examples\Tutorial directory. 12. Select File»Close Project to close the project. Moving and Deleting Steps The steps in SignalExpress projects depend on input data, which means steps can operate only on signals exported from previous steps in the Project View. When you click the Input signal pull-down menu on the Input tab of the Step Setup dialog box of a ste
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4 Working with Signals You can use LabVIEW SignalExpress to generate and analyze signals to evaluate designs without programming. This chapter teaches you how to work with signals in LabVIEW SignalExpress, including how to plot signals on graphs, import signals from a file, interactively align and compare two signals, and save signals to a file. Graphing Signals Complete the following steps to plot signals in a sample project and examine the signals visually using cursors. 1. Select File»Op
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Chapter 4 Working with Signals 6. Right-click the new graph and select Visible Items»Cursors from the shortcut menu to display two interactive cursors, as shown in Figure 4-1. Figure 4-1. Signals.seproj As you drag the cursors, LabVIEW SignalExpress displays the x and y values of the cursors in the cursor table at the bottom of the Data View. 7. Select File»Save Project As and save the project as MySignals.seproj in the SignalExpress\Examples\ Tutorial directory. Getting Started with LabVI
