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TM
LabVIEW
Order Analysis Toolset
User Manual
LabVIEW Order Analysis Toolset User Manual
August 2003 Edition
Part Number 322879B-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 0 662 45 79 90 0, Belgium 32 0 2 757 00 20, Brazil 55 11 3262 3599, Canada (Calgary) 403 274 9391, Canada (Montreal) 514 288 5722, Canada (Ottawa) 613 233 5949, Canada (Québec) 514 694 8521, Canada (Toronto) 905 785 0085, Canada (Vancouver) 514 685 7530, Ch
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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 per
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Contents About This Manual How to Use This Manual ...............................................................................................vii Conventions ...................................................................................................................vii Related Documentation..................................................................................................viii Chapter 1 Introduction to the LabVIEW Order Analysis Toolset Overview of the LabVIEW Order Analy
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Contents Chapter 3 Gabor Transform-Based Order Tracking Overview of Gabor Order Analysis............................................................................... 3-1 Extracting the Order Components................................................................................. 3-3 Masking .........................................................................................................................3-5 Extracting Orders ............................................................
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About This Manual This manual provides information about the LabVIEW Order Analysis Toolset, including system requirements, installation, and suggestions for getting started with order analysis and the toolset. The manual also provides a brief discussion of the order analysis process and the algorithm used by the LabVIEW Order Analysis Toolset. How to Use This Manual If you are just beginning to gain experience with order analysis, read Chapter 2, Order Analysis, of this manual and experime
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About This Manual bold Bold text denotes items that you must select or click in the software, such as menu items and dialog box options. Bold text also denotes the names of parameters, dialog boxes, sections of dialog boxes, windows, menus, palettes, and front panel controls and buttons. italic Italic text denotes variables or cross references. monospace Text in this font denotes text or characters that you should enter from the keyboard, sections of code, programming examples, and syntax ex
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1 Introduction to the LabVIEW Order Analysis Toolset This chapter introduces the LabVIEW Order Analysis Toolset and the Order Analysis Start-Up Kit, outlines system requirements, and gives installation instructions. Overview of the LabVIEW Order Analysis Toolset The LabVIEW Order Analysis Toolset is a collection of virtual instruments (VIs) for LabVIEW. These VIs help you measure and analyze noise or vibration signals generated by rotating machinery by enabling you to perform the following
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Chapter 1 Introduction to the LabVIEW Order Analysis Toolset application is built with components found in the LabVIEW Order Analysis Toolset. The order analysis application provides an example of how the LabVIEW Order Analysis Toolset can help you successfully complete analysis projects. The simple processes included in the order analysis application enable you to perform data acquisition, tachometer analysis, tachless speed profile generation, order analysis, and online monitoring of nois
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Chapter 1 Introduction to the LabVIEW Order Analysis Toolset System Requirements You must have LabVIEW 6.1 or later Full Development System or Professional Development System installed to run the LabVIEW Order Analysis Toolset. Note Refer to the LabVIEW Release Notes for the required system configuration for LabVIEW. Note Order analysis is a memory-intensive task, especially when you display spectral maps. Increasing the amount of RAM in your system can significantly increase system perform
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Chapter 1 Introduction to the LabVIEW Order Analysis Toolset Example VIs If you have experience with order analysis, the example VIs, located in theexamples\Order Analysis directory, can help you learn how to use the LabVIEW Order Analysis Toolset. The example VIs illustrate the following LabVIEW Order Analysis Toolset functions for both analog and digital tachometer signal processing: Acquiring data Presenting data Gabor order tracking Resample order tracking The example VIs use VIs
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Chapter 1 Introduction to the LabVIEW Order Analysis Toolset set to DAQ and you click the Run button on the front panel of the example VI, one of the following VIs opens: Acquire Data (Analog Tach) VI Acquire Data with PXI 4472 and TIO VI Refer to the Acquire Data (Analog Tach) VI section for information about the Acquire Data (Analog Tach) VI and the Acquire Data with PXI 4472 and TIO VI section for information about the Acquire Data with PXI 4472 and TIO VI. Acquire Data (Analog Tach)
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Chapter 1 Introduction to the LabVIEW Order Analysis Toolset tachometer signal and S&V for the sound or vibration sensor. After choosing data acquisition settings, enter the number of pulses you want the tachometer to generate per revolution in the Tach Pulse/Rev text box. Use the controls in the Channel Info section of the Configuration tab to specify the channel information for the sound or vibration sensor. After configuring the DAQ device, click the Acquisition tab, shown in Figure 1-2.
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Chapter 1 Introduction to the LabVIEW Order Analysis Toolset Figure 1-3. Acquire Data with PXI 4472 and TIO VI Configuration Tab Use the Configuration tab of the Acquire Data with PXI 4472 and TIO VI, shown in Figure 1-3, to configure the DAQ devices. Use one of the counters on a TIO device to receive TTL-compatible tachometer pulses. Use the controls in the TIO Board Setting (Digital Tach Signal) section of the Configuration tab to configure the TIO device. Use an NI PXI-4472 to acquire
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Chapter 1 Introduction to the LabVIEW Order Analysis Toolset Figure 1-4. Acquire Data with PXI 4472 and TIO VI Acquisition Tab The Acquisition tab, shown in Figure 1-4, allows you to acquire and observe data. Click the Acquire button to acquire data. Continue to configure the data acquisition and acquire data until you acquire the data you want. Click the OK button to return to the front panel of the example VI to analyze the data. LabVIEW Order Analysis Toolset User Manual 1-8 ni.com
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2 Order Analysis This chapter gives brief descriptions of the need for order analysis, the basic concepts of order analysis, the effect of rotational speed on order identification, and the different order analysis methods. Order Analysis Definition and Application When it is impossible or undesirable to physically open up a system and study it, you often can gain knowledge about the system by measuring and analyzing signals associated with the system. For example, physicists and chemists us
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Chapter 2 Order Analysis vibration signals. The frequency-domain representations of noise and vibration behave as harmonics of the machine rotational speed. In many industries, the harmonics related to the rotational speed are referred to as orders. The corresponding harmonic analysis is called order analysis. The harmonic at the same frequency as that of the rotational speed is the first order; the harmonic at twice the frequency of the rotational speed is the second order and so on. The
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Chapter 2 Order Analysis Assuming that speed remains constant during data acquisition, you can use the following equations to switch between the frequency domain and the order domain. RPM Frequency = --- ---- ---- - - ×Order 60 60 ---- ---- --- - - Order = Frequency × RPM Orders often reflect the physical characteristics of rotating machines. As in classical harmonic analysis, by analyzing the phase and amplitude relationships between different orders, you often can discover a great deal ab
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Chapter 2 Order Analysis Like classical harmonic analysis, order analysis is a powerful tool for gaining a better understanding of the condition of rotating machinery. However, compared to harmonic analysis, order analysis is more effective for the analysis of rotating machinery because you can use order analysis when a machine runs at a constant speed and when the rotational speed varies. As described in the Effect of Rotational Speed on Order Identification section, harmonic analysis is
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Chapter 2 Order Analysis Spectrum STFT 570 500 450 400 350 300 250 200 150 100 50 0 31.9 31.9 31.9 Figure 2-3. PC Fan Running at Constant Speed The bottom plot in Figure 2-3 depicts the tachometer pulses and the signal from an accelerometer mounted on the PC fan. The plot on the left in Figure 2-3 illustrates a conventional power spectrum based on the fast Fourier transform (FFT). The upper-right plot in Figure 2-3 shows the frequency-time spectral map computed from the short-time Fourier