Data Acquisition and Signal Conditioning Course Manual

1 data Acquisition and Signal Conditioning Course ManualCourse Software Version 2003 EditionPart Number 320733K-01 data Acquisition and Signal ConditioningCopyright 1995 2003 national instruments Corporation. All rights the copyright laws, this publication may not be reproduced or transmitted in any form, electronic or mechanical, including photocopying, recording, storing in an information retrieval system, or translating, in whole or in part, without the prior written consent of national instruments , DAQ-STC , FieldPoint , IMAQ , IVI , LabVIEW , Measurement Studio , national instruments , NI , NI-Motion , , NI-DAQ , NI-IMAQ , NI-PGIA , RTSI , and SCXI are trademarks of national instruments and company names mentioned herein are trademarks or trade names of their respective patents covering national instruments products, refer to the appropriate location.

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3 United Kingdom 44 0 1635 523545 national instruments CorporationiiiData Acquisition and Signal ConditioningContentsStudent GuideA. About This Manual .. ixB. What You Need to Get Started .. xC. Installing the Course xiD. Course Goals and Non-Goals ..xiiE. Course Conventions .. xiiiLesson 1 Overview of Transducers, Signals, and Signal ConditioningA. DAQ System Overview .. 1-2B. Transducers .. 1-3C. 1-4D. Signal Conditioning Overview .. 1-12 Summary .. 1-17 Lesson 2 data Acquisition Hardware and SoftwareA. DAQ Hardware Overview .. 2-2B. Components of a DAQ Device .. 2-7C. Configuration Considerations ..2-13D. Grounding 2-19E. Types of Measurement Systems .. 2-21F. Measuring Signal Sources .. 2-26G. DAQ Software .. 2-33H. NI-DAQ .. 2-34I. Measurement & Automation Explorer.

4 2-36J. Overview of NI-DAQmx VIs ..2-49K. NI-DAQmx Task State Model .. 2-53 Summary .. 2-58 Lesson 3 TriggeringA. Triggering .. 3-2 Summary .. 3-11 ContentsData Acquisition and Signal 4 Analog InputA. Analog Input .. 4-2B. Anti-aliasing Filters .. 4-7C. Using the DAQmx Read VI .. 4-11D. DAQ Device Architectures .. 4-17E. Multiple-Point (Buffered) AnaIog 4-23F. Continuous Acquisition Flowchart .. 4-33 Summary .. 4-49 Lesson 5 Signal ConditioningA. Overview of Signal Conditioning .. 5-2B. Signal Conditioning 5-3C. Signal Conditioning Functions .. 5-11D. 5-21E. Isolation .. 5-33F. Transducer Conditioning .. 5-36G. 5-37H. Strain .. 5-46I. Strain Gauge .. 5-47J. Signal Conditioning for Strain Gauges .. 5-53K. Strain Gauge Equations .. 5-56 Summary.

5 5-64 Lesson 6 Signal ProcessingA. Discrete Fourier Transform (DFT) and Fast Fourier Transform (FFT).. 6-2B. Frequency Spacing and Symmetry of the DFT/FFT .. 6-6C. Power Spectrum .. 6-11D. About Spectral Leakage and Smoothing Windows .. 6-19E. Characteristics of Different Types of Window Functions .. 6-23F. Determining Which Type of Window To 6-30G. 6-36H. Ideal Filters .. 6-37I. Practical (Nonideal) Filters .. 6-39J. Advantages of Digital Filters over Analog Filters .. 6-41K. IIR and FIR Filters .. 6-42L. Infinite Impulse Response Filters .. 6-44M. IIR Filter Comparison .. 6-50N. Transient Response of IIR Filters .. 6-52O. Finite Impulse Response 6-60 Summary .. 6-62 Contents national instruments CorporationvData Acquisition and Signal ConditioningLesson 7 Analog OutputA.

6 Analog Output 7-2B. Using the DAQmx Write VI .. 7-4C. Multiple-Point (Buffered) AO VIs .. 7-10D. Finite Buffered Generation .. 7-11E. Continuous Buffered Generation .. 7-21 Summary .. 7-32 Lesson 8 Digital I/OA. Digital 8-2B. Digital I/O .. 8-4 Summary .. 8-12 Lesson 9 CountersA. Counter Signals .. 9-2B. Counter Chips .. 9-5C. Counter I/O .. 9-6D. Edge Counting .. 9-8E. Advanced Edge Counting .. 9-12F. Pulse Generation .. 9-17G. Pulse Measurement .. 9-25H. Frequency Measurements .. 9-30I. Position 9-35 Summary .. 9-40 Lesson 10 SynchronizationA. Explicit State Transitions .. 10-2B. Single Device 10-8C. Multiple Device Synchronization .. 10-29 Summary .. 10-38 Appendix AA. Theory of Common Transducers .. A-2B. Analog I/O Circuitry .. A-8 national instruments CorporationviiData Acquisition and Signal ConditioningStudent GuideThank you for purchasing the data Acquisition and Signal Conditioning Course kit.

7 This Course Manual and accompanying software are used in the three-day, hands-on data Acquisition and Signal Conditioning can apply the full purchase of this Course kit toward the corresponding Course registration fee if you register within 90 days of purchasing the kit. Visit for online Course schedules, syllabi, training centers, and class data Acquisition and Signal Conditioning Course is part of a series of courses designed to build your proficiency with LabVIEW and help you prepare for exams to become an NI Certified LabVIEW Developer and NI Certified LabVIEW Architect. The following illustration shows the courses that are part of the LabVIEW training series. Refer to for more information about NI GuideData Acquisition and Signal LabVIEWB asics I:IntroductionLabVIEWB asics II:DevelopmentLabVIEW Advanced:Performance &CommunicationLabVIEW Instrument ControlData Acquisition andSignal ConditioningStudent Guide national instruments CorporationixData Acquisition and Signal ConditioningA.

8 About This ManualThis Course Manual teaches you the fundamentals of data Acquisition (DAQ) and Signal Conditioning and introduces techniques you can implement in real-world Course also expands on good LabVIEW programming style issues from the LabVIEW Basics I: Introduction and LabVIEW Basics II: Development courses and discusses several programming guidelines you can use in your data Acquisition and Signal Conditioning applications. This Course Manual assumes that you are familiar with Windows, that you have experience writing algorithms in the form of flowcharts or block diagrams, and that you have taken the LabVIEW Basics I: Introduction Course or you have familiarity with all the concepts contained therein. This Course also assumes you have approximately one year or more of LabVIEW development Course Manual is divided into lessons, each covering a topic or set of topics.

9 Each lesson consists of the following: An introduction that describes the purpose of the lesson and what you will learn A description of the topics in the lesson A set of exercises to reinforce those topics A summary that outlines important concepts and skills taught in the lessonSeveral exercises in this Manual use a plug-in multifunction DAQ device connected to a DAQ Signal Accessory, and either SCXI or SCC Signal Conditioning equipment .Student GuideData Acquisition and Signal What You Need to Get StartedBefore you use this Course Manual , make sure you have all the following items: Computer running Windows 98 or later LabVIEW Full Development System or Professional Development System or laterNoteThis Course assumes you are using the default installation of LabVIEW.

10 If you have changed the palette views from the default settings, some palette paths described in the Course might not match your settings. To reset palette views to LabVIEW defaults, select Tools Options and select Controls/Functions Palettes from the top pull-down menu. Set Palette View to Express and set Format to Standard. Click the OK button to apply the changes and close the dialog box. MIO Series DAQ board DAQ Signal Accessory and cable SCXI chassis, modules, terminal blocks, and transducers as described in Lesson 5, Signal Conditioning data Acquisition and Signal Conditioning Course CD, containing the following files:DirectoryDescriptionExercisesConta ins all the VIs and support files needed to complete the exercises in this courseSolutionsContains completed versions of the VIs you build in the exercises for this courseStudent Guide national instruments CorporationxiData Acquisition and Signal ConditioningC.