National Instruments SCXI-1125 manual

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Índice do manual

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    SCXI TM SCXI-1125 User Manual SCXI-1125 User Manual April 2008 372425B-01[...]

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    Support Worldwide Technical Support and Product Info rmation ni.com National Instruments Corporate Headquarters 11500 North Mopac Expressway Aust in, 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 8 6 21 5050 9800[...]

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    Important Information Warranty The SCXI-1125 is warranted against defects in materials and wo rkma nship for a p eriod of one year from the date of shipment, as evidenced by receipts or other documentati on. National Instruments wil l, at its option, repair or replace equipment that proves to be defect ive during the warranty period. This warrant y[...]

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    Conventions The follo wing con ventions are used in this manual: < > Angle brackets that contain numbers separated b y an ellipsis represent a range of v alues associated with a bit or signal name—for example, P0.<3..0>. » The » symbol leads you through nested menu items and dialog box options to a final action. The sequence File»P[...]

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    © National Instruments Cor poration v SCXI-1125 User Manual Contents Chapter 1 About the SCXI-1125 What You Need to Get Started .............. .............. .............. .............. .............. .............. .. 1-1 National Instruments D ocumentatio n ............... .............. ............ .............. .............. ....... 1-2 I[...]

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    Contents SCXI-1125 User Manual vi ni.com Chapter 3 Configuring and Testing SCXI-1125 Software-Configurable Settings ........ ................. .............. .............. ............ 3-1 Common Software-Configurable Settings ...... .............. .............. .............. ...... 3-1 Filter Bandwidth ..... .............. .............. ......[...]

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    Contents © National Instruments Corpor ation vii SCXI-1125 User Manual Configuring Channel Properties.................. .............. ................. ....... 5-8 Acquiring, Analyzing, and Presenting ...................... .............. .......... 5-9 Completing the Application ..................... .............. .............. ............. 5[...]

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    Contents SCXI-1125 User Manual viii ni.com Appendix A Specifications Appendix B Using SCXI Channel Strings with Tr aditional NI-DAQ (Legacy) 7.0 or Later Appendix C Removing the SCXI-1125 Appendix D Common Questions Glossary Index Figures Figure 2-1. Connecting a Ground-Referenced Si gnal ........ .............. .............. ......... 2-2 Figure [...]

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    Contents © National Instruments Corpor ation ix SCXI-1125 User Manual Tables Table 2-1. Front Signal Pin Assignments ..................... .............. .............. ........... .. 2-6 Table 2-2. Rear Signal Pin Assignments ......... ........... .............. .............. .............. .. 2-8 Table 5-1. Extended Gain and Range Usin g the SC[...]

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    © National Instruments Corpor ation 1-1 SCXI-1125 User Manual 1 About the SCXI-1125 This chapter introduces the SCX I-1125 module and explain s how to install the software and hardware. The SCXI-1125 is an eight-channel isolated analog input conditioning module with programmable gain and f i lter settings on each channel and is jumperless. Each ch[...]

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    Chapter 1 About the SCXI-1125 SCXI-1125 User Manual 1-2 ni.com Note For maximum allow able voltage for a particul ar terminal block refer to T able A-2, Terminal Block Maximum Volt ages . – SCXI or PXI/SCXI combination chassis – One of the follo wing: • E/M Series D A Q device • SCXI-1600 module – A computer if using an SCXI chassis – C[...]

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    Chapter 1 Abou t the SCXI-1125 © National Instruments Corpor ation 1-3 SCXI-1125 User Manual • The SCXI Quick Start Guide —This documen t contains a q uick ov ervie w for setting up an SCXI chassis, installing SCXI modul es and terminal blocks, and attaching sen sors. It also describes setting up the SCXI system in MAX. • The SCXI hardware u[...]

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    Chapter 1 About the SCXI-1125 SCXI-1125 User Manual 1-4 ni.com Installing Application Software, NI-DAQ, and the DAQ Device Refer to the DAQ Getting Started Guide packaged with the NI-DAQ software to install your application so ftware, NI-DAQ driver soft ware, and the DAQ device to which you will connect the SCXI-1 125. NI-DAQ 7.0 or later is requir[...]

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    Chapter 1 Abou t the SCXI-1125 © National Instruments Corpor ation 1-5 SCXI-1125 User Manual Connecting the SCXI- 1125 to a n E/M Series DAQ Device for Parallel Scanning This configuration allows you to route all eight channels of the SCXI-1125 in parallel to eight i nput channels of the E/M Series DAQ device to which it is connected. In this mode[...]

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    Chapter 1 About the SCXI-1125 SCXI-1125 User Manual 1-6 ni.com Manually Adding Modules in NI-DAQmx If you did not auto-detect the SCXI modules, you must manually add each of the modules. Refe r to the S CXI Quick Start Guide to manuall y add modules. Note NI recommends auto-detecting mod ules for the first time conf iguration of the chassis. Instal[...]

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    Chapter 1 Abou t the SCXI-1125 © National Instruments Corpor ation 1-7 SCXI-1125 User Manual T roubleshooting the Self-T est V erification If the Self-Test Verification did not verify the chassi s configuration, complete the step s in this section to troubleshoot th e SCXI conf iguration. T roubleshooting in NI-DAQmx • If you get a Verify SCXI C[...]

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    Chapter 1 About the SCXI-1125 SCXI-1125 User Manual 1-8 ni.com module following the steps listed in the SCXI Quick Start Guide . Click OK . b . If another module appears wh ere the cabled module should be, click the drop-down listbox next to the correct slot and select the cabled module. A message box appears asking you to confirm the module replac[...]

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    © National Instruments Corpor ation 2-1 SCXI-1125 User Manual 2 Connecting Signals This chapter describes the input and output signals connect ions to the SCXI-1125 module with the m odule front connector and the rear signal connector. This chapter also incl udes specifications and connection instructions for the signals on the SCXI-112 5 module c[...]

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    Chapter 2 Connecting Signals SCXI-1125 User Manual 2-2 ni.com completely isolated from other channels. Y o u can operate with common-mode voltage le vels up to 300 V rms . Figures 2-1 through 2-4 show signal connection method s that giv e the highest noise immunit y . Ground-Referenced Signal When the negative input signal line is connect ed either[...]

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    Chapter 2 Connecting Signals © National Instruments Corpor ation 2-3 SCXI-1125 User Manual Floating Signal In cases where both signal lines at the transducer end are floating and no common-mode voltage exists, establ ish an earth connection at the SCXI-1125 by connecting the negati ve input line to chassis ground in the terminal block, as shown in[...]

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    Chapter 2 Connecting Signals SCXI-1125 User Manual 2-4 ni.com AC-Coupling You can have an application wh ere you wish to measure only A C voltages and remove the D C component o f a signal before amplification and sampling. In su ch cases, you can connect a capacitor in series with one or both input terminals of the SCXI -1125, as shown in Figures [...]

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    Chapter 2 Connecting Signals © National Instruments Corpor ation 2-5 SCXI-1125 User Manual The value of the bias resistor should be between 100 k Ω and 1 M Ω . An added DC offset v oltage results, due to input bias current flowing through the bias resistor . For ex ample, with a 1 M Ω bias resistor and the specified maximum input bias curren t [...]

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    Chapter 2 Connecting Signals SCXI-1125 User Manual 2-6 ni.com Table 2-1. Front Signal Pin Assignments Front Connect or Diagram Pin Number Column A Column B Column C NC means no connection — means no pin 32 AI 0 + — AI 0 – 31 ——— 30 AI 1 + — AI 1 – 29 ——— 28 NC — NC 27 ——— 26 AI 2 + — AI 2 – 25 ——— 24 AI 3 + ?[...]

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    Chapter 2 Connecting Signals © National Instruments Corpor ation 2-7 SCXI-1125 User Manual T emperature Sensor Connection Pin C4 on the front signal connector is used to connect to a terminal block temperature sensor. The temp erature sensor channel is not isolated and is referenced to the chassis ground. Th e connection is overvoltage protected t[...]

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    Chapter 2 Connecting Signals SCXI-1125 User Manual 2-8 ni.com Table 2-2. Rear Signal Pin Assignments Rear Connector Diagram Signal Name Pin Number Pin Number Signal Name NC means no connection AI GND 1 2 AI GND CH 0 + 3 4 CH 0 – CH 1 + 5 6 CH 1– CH 2 + 7 8 CH 2 – CH 3 + 9 10 CH 3 – CH 4 + 11 12 CH 4 – CH 5 + 13 14 CH 5 – CH 6 + 15 16 CH[...]

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    © National Instruments Corpor ation 3-1 SCXI-1125 User Manual 3 Configuring and T esting This chapter discusses configuring the SCXI-1125 in MAX for use with either NI-DAQmx or Tradi tional NI-D AQ (Legacy), creating and testing a virtual channel, global channel or task. For mo re information on the relationship between the settings and th e measu[...]

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    Chapter 3 Configuring and T esting SCXI-1125 User Manual 3-2 ni.com Connecting the SCXI-112 5 in an SCXI Chassis to an E/M Series DAQ Device for Multiplexed Scanning Refer to the SCXI Qu ick Start Guid e to install the cable adapter and connect the SCXI modules to the DAQ device. If you have already installed the appr opriate software, refer to Cha[...]

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    Chapter 3 Configuring and T esting © National Instruments Corpor ation 3-3 SCXI-1125 User Manual NI-DAQmx In NI-DAQmx, you can configure so ft ware settings such as filter bandwidth and gain/input signal range in the following ways: • T ask or g lobal channel i n MAX • Functions in your application Note All software-configurable settings are n[...]

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    Chapter 3 Configuring and T esting SCXI-1125 User Manual 3-4 ni.com 4. Select Analog Input . 5. Select Voltage . 6. If you are creating a task, you can se lect a range of channels by holding do wn the <Shift> key while select ing the channels. Y ou can select multiple individual channels by holding do wn the <Ctrl> key while selecting c[...]

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    Chapter 3 Configuring and T esting © National Instruments Corpor ation 3-5 SCXI-1125 User Manual • Gain/input signal range—configure gain using module propert ies. When you set the minimum and maxi mum range of the virt ual channel, the dri ver selects the be st gain. The default gain set ting for T raditional NI-DA Q (Legacy) is 1000. • T e[...]

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    Chapter 3 Configuring and T esting SCXI-1125 User Manual 3-6 ni.com Creating a Virtual Channel To create a virtual channel, complete the following steps: 1. Right-click Data Neighborhood and select Create New . 2. Select Traditional NI-DAQ Virtual Channel and click Finish . 3. Click Add Channel . 4. Select Analog Input from the drop-down list and c[...]

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    Chapter 3 Configuring and T esting © National Instruments Corpor ation 3-7 SCXI-1125 User Manual 8. Click the Device tab . 9. Enter the appropriate information on the Device tab . 10. Click the Test button. 11. Click the Start button. 12. After you hav e completed verifying the channels, click the Stop button. Y ou hav e now v erified the SCXI-112[...]

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    Chapter 3 Configuring and T esting SCXI-1125 User Manual 3-8 ni.com Complete the following steps to use chan nel strings in verifying the signal: 1. Expand Devices and Interfaces . 2. Expand Traditional NI-DA Q Devices . 3. Right-click the appropriate E Series D A Q device. 4. Click Test Panels . 5. Enter the channel string. 6. Enter the input limi[...]

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    © National Instruments Corpor ation 4-1 SCXI-1125 User Manual 4 Theor y of Operation The section includes a brief overview and a detailed discussion of the circuit features of the module. The two major modes of operati on, multiplexed and parallel mo de, are discussed. Refer to Figure 4-1 while reading this section. Figure 4-1. SCXI-1125 Block Dia[...]

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    Chapter 4 Theory of Operat ion SCXI-1125 User Manual 4-2 ni.com Refer to the Configurabl e Settings in MAX section of Chapter 3, Configuring and Testi ng , for more information about programmatically setting gain using range settings in MAX. For more information about programmatically setting gain using range settings in NI-DA Qmx and T raditional [...]

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    Chapter 4 Theor y of Operation © National Instruments Corpor ation 4-3 SCXI-1125 User Manual Multiplexed Hardware Operation Theory When you configure a module fo r multiplexed mode o peration, the routing of multiplexed signals to the E/M Series DAQ devi ce depends on which module in the SCXI sy stem is cabled to the E/M Series DAQ device. There a[...]

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    Chapter 4 Theory of Operat ion SCXI-1125 User Manual 4-4 ni.com Theor y of Parallel Hardware Operation In parallel mode, the CH0 signal on t he rear signal connector is configured as the output of t he SCXI-1125 an alog input channel 0. The rear signal connector carries each of the analog outputs of the SCXI-1125 to the connected DAQ device. You ca[...]

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    © National Instruments Corpor ation 5-1 SCXI-1125 User Manual 5 Using the SCXI-1125 This chapter discusses typical applicat ions for the SCXI-1125. While this list is not co mprehensive, it provides some g uidance on how to improve measurement accuracy for some of the most popular applications of the SCXI-1125. Advanced o perations su ch as calibr[...]

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    Chapter 5 Using the SCXI-1125 SCXI-1125 User Manual 5-2 ni.com thermocouple junction v oltage and te mperature, this v oltage con version (linearization) is best do ne through software. NI-D A Q has built-in scaling for most ther mocouple types. In NI-DA Qmx, you can create a thermocouple task or global channel. In Traditional NI-D A Q (Legacy), yo[...]

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    Chapter 5 Using the SCXI-1125 © National Instruments Corpor ation 5-3 SCXI-1125 User Manual Complete the fo llo wing steps to cal cu late the ov erall temperature error using the SCXI-1125 w ith an E Series MIO DA Q device: 1. Based on the required temperature range and the type of sensor, determine the gain to use. For example, using a K-type the[...]

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    Chapter 5 Using the SCXI-1125 SCXI-1125 User Manual 5-4 ni.com Making High-V oltage Measurements Another common use of the SCXI-1125 is to make measurements up to 1000 VDC. Making measurements beyond ± 5 V requires use of the an attenuator terminal block. The SCX I-1327 and SCXI-1313A terminal blocks have a selectable attenuator for choo sing betw[...]

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    Chapter 5 Using the SCXI-1125 © National Instruments Corpor ation 5-5 SCXI-1125 User Manual The ov erall input impedance is reduced when attenuating the input, but this is acceptable in most applications. Refer to terminal block installation guides for more informatio n. Appendix A, Specifications , shows how the analog input specifications are af[...]

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    Chapter 5 Using the SCXI-1125 SCXI-1125 User Manual 5-6 ni.com Figure 5-1. T ypical Program Flowchart Ye s Create Channel (Application Specific) Adjust Timing Settings Create a T ask Programmatically Create T ask in D A Q Assistant or MAX No Hardware Timing/T rigger ing? Create T ask Using D A Q Assistant? No Y es No Ye s Configure Channels Fur the[...]

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    Chapter 5 Using the SCXI-1125 © National Instruments Corpor ation 5-7 SCXI-1125 User Manual General Discussion of T ypical Flowchart The following sections discuss briefly considerations for a few of the steps in Figure 5-1. These sections giv e an overview of some of the options and features available when pr ogramming with NI-DAQmx. Creating a T[...]

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    Chapter 5 Using the SCXI-1125 SCXI-1125 User Manual 5-8 ni.com time. For continuous acquisition, you must use a while loop around the acquisition componen ts e ven if you conf igured the task for continuous acquisition using MAX or the DA Q Assistant. For continuous and buf fered acquisitions, you can set the acqui sition rate and the number of sam[...]

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    Chapter 5 Using the SCXI-1125 © National Instruments Corpor ation 5-9 SCXI-1125 User Manual Acquiring, Analyzin g, and Presenting After configuring the task and channels , you can start the acquisition, read measurements, analyze the data return ed, and display it according to the needs of your applicatio n. Typical meth ods of analysis include di[...]

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    Chapter 5 Using the SCXI-1125 SCXI-1125 User Manual 5-10 ni.com Table 5-4. Pro gramming a T ask in LabVIEW Flowchart Step VI or Program Step Create T ask in DA Q Assistant Create a DAQmx Task Name Constant located on the Controls»Modern»I/O»DAQmx Name Controls subpalette, right-click it, and select New NI-DAQmxTask (MAX...) . Create a T ask Prog[...]

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    Chapter 5 Using the SCXI-1125 © National Instruments Corpor ation 5-11 SCXI-1125 User Manual Using a DAQmx Channel Prop erty Node in LabVIEW You can use property no des in LabVIEW to manual ly configure the channels. To create a LabVIEW prope rty node, complete the following steps: 1. Launch LabVIEW . 2. Create the property node in a new VI or in [...]

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    Chapter 5 Using the SCXI-1125 SCXI-1125 User Manual 5-12 ni.com 7. Change the property to read or write to eith er get the property or write a new value. Right-click the property , go to Change To , and select Write , Read , or De fault Val ue . 8. After you hav e added the property to the property node, rig ht-click the terminal to change the attr[...]

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    Chapter 5 Using the SCXI-1125 © National Instruments Corpor ation 5-13 SCXI-1125 User Manual Follo w the general programming flowch art or open an e xample to bu ild a basic virtual channel. Y ou can use property nodes in LabVIEW t o control, configure, and customize the NI-D A Qmx task and SCXI-1125. T o create a LabVIEW property n ode, complete [...]

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    Chapter 5 Using the SCXI-1125 SCXI-1125 User Manual 5-14 ni.com T ext Based ADEs You can use text based ADEs such as LabWindows/CVI, Measurement Studio, Visual Basic, .NET, and C# to create code for using the SCXI-1125. LabWindows/CVI LabWindows/CVI work s with the DAQ Assistant in MAX to generate code for a task. You can then use th e appropriate [...]

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    Chapter 5 Using the SCXI-1125 © National Instruments Corpor ation 5-15 SCXI-1125 User Manual Note This is no t a complete list of NI-D A Q mx properties and does not include ev ery property you may need to configure your application. For a complete list of NI-DA Qmx properties and more information on NI-DA Qmx properties, refer to your ADE help fi[...]

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    Chapter 5 Using the SCXI-1125 SCXI-1125 User Manual 5-16 ni.com T raditional NI-DAQ (Legacy) in LabVIEW LabVIEW is a graphical programming envi ronment for test and measurement application develo pment with built-in easy to use tools for data acquisition, analysis, and display. You can use funct ional graphical blocks called subVIs to easily create[...]

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    Chapter 5 Using the SCXI-1125 © National Instruments Corpor ation 5-17 SCXI-1125 User Manual T ypical Program Flow After you have determined how you want to address the chann els and whether you want to co nfigure the SCXI-1125 in MAX o r LabVIEW, you can design your applicat ion using a t ypical program flow such as the one shown in Figure 5 -3. [...]

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    Chapter 5 Using the SCXI-1125 SCXI-1125 User Manual 5-18 ni.com Configure the SCXI- 1125 Settings Using T r aditio nal NI-DAQ (Legacy) in LabVIEW You can configure SCXI-1125 settings in MAX using the virtual chan nel. To configure and control the SCXI-1125 from LabVIEW , use the AI Parameter VI. You can find AI Parameter VI in the function subpalet[...]

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    Chapter 5 Using the SCXI-1125 © National Instruments Corpor ation 5-19 SCXI-1125 User Manual An example of using the AI Parameter VI to control an SCXI-1125 is sho wn in Figure 5 -4. Figure 5-4. Using the AI Parameter VI to Set Up the SCXI-1125 Configure, Start Acqu isition, and T ake Read ings Using T raditional NI-DAQ (Legacy) in LabVIEW After y[...]

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    Chapter 5 Using the SCXI-1125 SCXI-1125 User Manual 5-20 ni.com Convert Scaling Using T raditional NI-DAQ ( Legacy) in LabVIEW If you need scaling, you can either use an analog input voltage virtual channel with a custom scale configur ed in MAX or SCXI channel strings, and provide scaling in your LabVIEW appl ication. If you are using SCXI channel[...]

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    Chapter 5 Using the SCXI-1125 © National Instruments Corpor ation 5-21 SCXI-1125 User Manual T raditional NI-DAQ (Legac y) in T ext-Based ADEs NI text-based ADEs, such as La bWindows/CVI, Measurement St udio for Microsoft Visual Basic, and Measurement Studio for Microsoft Visual C++, offer help in the dev elopment of test and measurement applicati[...]

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    Chapter 5 Using the SCXI-1125 SCXI-1125 User Manual 5-22 ni.com Note NI strongly recommends monitorin g the bu ilt-in error status of each NI-D A Q function. The NI-DA Q C API provides the NIDAQErrorHandler function, which ensures that a specified NI-D A Q function executed properly , and assists in handli ng error messages and reporting. Configure[...]

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    Chapter 5 Using the SCXI-1125 © National Instruments Corpor ation 5-23 SCXI-1125 User Manual Perform Offset Null Compensation Us ing T raditional NI-DAQ (Legacy) C API After configuring th e system set tings and mod ule properties, you can perform an offset null compensation programm atically using SCXI_Calibrate . SCXI_Calibrate takes measurement[...]

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    Chapter 5 Using the SCXI-1125 SCXI-1125 User Manual 5-24 ni.com the data corresponds to a scanned channel for easier access by C applications. BASIC app licat ions need not call SCAN_Demux to rearrange two-dimensional arrays since these arrays are accessed in column-major order. For more information regarding each acquisition function, refer t o th[...]

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    Chapter 5 Using the SCXI-1125 © National Instruments Corpor ation 5-25 SCXI-1125 User Manual support virtual channels using Data Neighb orhood (DAQ Channel Wizard) in MAX. In LabWindows/CVI, C, or C++ development environments, several NI-DAQ function calls need to be made to set up each module involved in the scan, the chassis, a nd the E Series D[...]

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    Chapter 5 Using the SCXI-1125 SCXI-1125 User Manual 5-26 ni.com The last parameter , channel s , is the list of channels that are scanned for module z . It can hav e se veral forma ts: • ob x ! sc y ! md z ! n , where n is a single input channel. • ob x ! sc y ! md z ! n1:n2 , where n1 and n2 represent a sequential list of input channels, inclu[...]

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    Chapter 5 Using the SCXI-1125 © National Instruments Corpor ation 5-27 SCXI-1125 User Manual Note Y ou cannot mix virt ual channels with the SCXI channel str ings shown in the previous section. T o create a virtual channel for the SCXI-1125, insert a new analog input channel in the Data Neighb orhood path in MAX, name it, and then follow the softw[...]

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    Chapter 5 Using the SCXI-1125 SCXI-1125 User Manual 5-28 ni.com C and Low-Level DAQ Functions When using a C-based environment, se veral steps are needed to configure the SCXI-1125 for m ultiplexed scannin g. The followin g procedure outlines the steps for programming with th e low-level DAQ function calls: 1. Prepare the SCXI-1125 se ttings by eit[...]

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    Chapter 5 Using the SCXI-1125 © National Instruments Corpor ation 5-29 SCXI-1125 User Manual After parallel mode has been configured in software, you can scan the SCXI-1125 channels by entering the corresponding E Series D A Q device channels or a sequential SC XI channel string in the channel parameter in the analog input app lication. Y ou can a[...]

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    Chapter 5 Using the SCXI-1125 SCXI-1125 User Manual 5-30 ni.com Calibration The SCXI-1125 is shipped wit h a calibration certificate and is calibrate d by the factory to the specifications described in Appendix A , Specifications . Calibration constants are stored inside the calibration EEPR OM and provide software correction values that are used b[...]

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    Chapter 5 Using the SCXI-1125 © National Instruments Corpor ation 5-31 SCXI-1125 User Manual One-Point Offset Calibration To perform offset calibration on your m odu le, follow this procedure if you are using LabVIEW: 1. Make sure the D A Q de vice or DMM you are using has a v alid calibration and meets the accuracy specifications for your applica[...]

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    Chapter 5 Using the SCXI-1125 SCXI-1125 User Manual 5-32 ni.com If you are using a C-based ADE, use the following procedure to do an of fset calibration on t he SCXI-1125: 1. Make sure the D A Q device or DMM you are using has a valid calibration and meets the accuracy specifications for your application. 2. Use the NI-D A Q function SCXI_Calibrate[...]

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    © National Instruments Corpor ation A-1 SCXI-1125 User Manual A Specifications This appendix lists the specifications for the SCXI-1125 modules. These specifications are typical at 25 °C unless otherwise noted. Input Characteristics Note Refer to T ables 5-1 and 5-2 for extended range using the SCXI-1313 A, SCXI-1327, and TBX-1316. Table A-1. Inp[...]

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    Appendix A Specifications SCXI-1125 User Manual A-2 ni.com Overvoltage protection Isolated connector pins: Powered on and off......................... .±300 V Inputs protected ................ .............. .CH0..CH7 Non-isolated co nnector pins: Powered on and off......................... .+5.5V/– 0.5 V[...]

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    Appendix A Specifications © National Instruments Corpor ation A-3 SCXI-1125 User Manual Absolute Accuracy Nominal Range Overall Gain % of Read ing Offset System Noise (peak, 3 sigma) T emperature Drift Absolute Accuracy at Full Scale (mV) 1 Single Point A verage Ty p i c a l Max 4 Hz 10 kHz 4 Hz 10 kHz % of Reading/ ° C Offset (uV/ ° C) ±1000 V[...]

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    Appendix A Specifications SCXI-1125 User Manual A-4 ni.com ±10 mV 500 0.08 0.53 20 μ V 1.3 μ V 21.8 μ V 0.27 μ V 4.70 μ V 0.0027 1.0 μ V 80 μ V ±5 mV 1000 0.08 0.53 15 μ V 0.72 μ V 14.9 μ V 0.17 μ V 3.2 μ V 0.0027 0.7 μ V 45 μ V ±2.5 mV 2000 0.09 0.54 15 μ V 0.42 μ V 11.2 μ V 0.10 μ V 2.5 μ V 0.0027 0.6 μ V 31 μ V 1 Absolute[...]

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    Appendix A Specifications © National Instruments Corpor ation A-5 SCXI-1125 User Manual Analog Inputs Number of input channels ..................... . 8 differential Input range ................ .............. .............. . ± 2.5 mVDC to ±5 VDC Input coupling ......................... .............. . DC (or AC with SCXI-1305 or TBX-1329) Inp[...]

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    Appendix A Specifications SCXI-1125 User Manual A-6 ni.com Normal Mode Rejection, 50/6 0 Hz (NMRR) 4 Hz filter enabled .................. .........60 dB Crosstalk at 1kHz Adjacent channels ........ ........... .........–75 dB All other channels ..... .............. .........– 90 dB Input coupling Default ............. .............. ...........[...]

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    Appendix A Specifications © National Instruments Corpor ation A-7 SCXI-1125 User Manual Physical Figure A-1. SCXI-1125 Dimensions Weight ....................... .............. .............. . 641 g (22.6 oz) 3.0 cm (1.2 in.) 17.2 cm (6.8 in.) 18.8 cm (7.4 in.)[...]

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    Appendix A Specifications SCXI-1125 User Manual A-8 ni.com Maximum W orking Voltage Maximum voltage rating refers to the signal voltage plus the common mode voltage (Signal + common mode). V oltage of each input shall remain within 300 V of ground. Channel-to-earth ................... .............. ....300 V, Measurement Category II Channel-to-cha[...]

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    Appendix A Specifications © National Instruments Corpor ation A-9 SCXI-1125 User Manual Safety This product is designed to meet the requirements of the following standards of safety for electrical e quipment for measurement, control, and laboratory use: • IEC 61010-1, EN-61010-1 • UL 61010-1, CSA 61010-1 Note For UL and other safety certificat[...]

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    Appendix A Specifications SCXI-1125 User Manual A-10 ni.com Environmental Management National Instruments is comm itted to designing and manufacturing products in an environmentally responsible manner . NI recognizes that eliminating certa in hazardous substances from our products is beneficial not only t o the en vironmen t but also to NI customer[...]

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    © National Instruments Corpor ation B-1 SCXI-1125 User Manual B Using SCXI Channel Strings with T raditional NI-DAQ (Legacy) 7.0 or Later Note This appendix is n ot applicable if you use the virtual channels to configure and measure the SCXI channels. V irtual channels are configured using MAX. If you use virtual channels, you address the SCXI cha[...]

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    Appendix B Using SCXI Channel Strings with T raditional NI-DAQ (Legacy) 7.0 or Later SCXI-1125 User Manual B-2 ni.com channels is the list of channels that are scanned for module z . It can hav e se veral f ormats: • ob x ! sc y ! md z ! nx , where nx is a single input channel. • ob x ! sc y ! md z ! ( n0 , n2 ) , where n0 , n2 are indi vidual [...]

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    © National Instruments Corpor ation C-1 SCXI-1125 User Manual C Removing the SCXI-1125 This appendix explains ho w to remove the SCXI-1125 from MAX and an SCXI chassis. Note Figure C-1 shows an SCXI chassis, b ut the same steps are applicable to a PXI/SCXI combination chassis. Removing the SCXI-1125 from MAX T o remove a module from MAX, complete [...]

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    Appendix C Removi ng the SCXI-1125 SCXI-1125 User Manual C-2 ni.com 2. If the SCXI-1125 is th e module cabled to t he E Series D A Q d evice, disconnect the cable. 3. Remov e any terminal block that connects to the SCXI-1125 . 4. Rotate the thumbscrews that secu re the SCXI-1125 to the chassis counterclockwise until they are loose, but do not compl[...]

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    © National Instruments Corpor ation D-1 SCXI-1125 User Manual D Common Questions This appendix lists com mon questions related to the u se of the SCXI-1125. The SCXI-1125 is backwa rd compatible with the SCXI-1120 , but what are the major differences between the SCXI-1120 and the SCXI-1125? T able D-1 compares the major specifi cations and feature[...]

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    Appendix D Common Questi ons SCXI-1125 User Manual D-2 ni.com Which version of NI-DAQ is needed to work with the SCXI-1125 and how do I get the most current version of NI-DAQ? Y ou m ust hav e NI-D A Q 7.0 or later . V isit ni.com and follow the link, Download Software»Drivers and Updates»Search Drivers and Updates , and type in the ke ywor d NI-[...]

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    Appendix D Common Questions © National Instruments Corpor ation D-3 SCXI-1125 User Manual In LabVIEW , can I use different in put limits for the same SCXI-1125 channel if I repeat the channel in the SCXI channe l string array? No, the SCXI-1125 cannot dynamically change the gain settings during scanning. Therefore, channels with si milar input ran[...]

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    Appendix D Common Questi ons SCXI-1125 User Manual D-4 ni.com In LabVIEW , can I use a VI to change my f ilter setting? In NI-D A Qmx, you can change the filter settings using a D A Qmx Channel property node. In T raditional NI-DA Q (Legacy), there is no VI av ailable to do this. Y ou must use the configuration utility in MAX to configure the filte[...]

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    © National Instruments Corpor ation G-1 SCXI-1125 User Manual Glossar y Symbol Pref ix V alue pp i c o 1 0 – 12 nn a n o 1 0 – 9 μ micro 10 – 6 m mil li 10 – 3 k kilo 10 3 Mm e g a 1 0 6 Gg i g a 1 0 9 Tt e r a 1 0 12 Numbers/Symbol ° Degrees. ≥ Greater than or equal to. ≤ Less than or equal to. Ω Ohms. /P e r . % Percent. ± Plus o[...]

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    Glossary SCXI-1125 User Manual G-2 ni.com A A/D analog-to-digital absolute accuracy The maximum dif ference be tween the measured v alue from a data acquisition device and the true voltage applied to the input, typically specified as ± v oltage. A C alternating current ADC analog-to-digital con verter—An elect ronic device, often an integrated c[...]

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    Glossary © National Instruments Corpor ation G-3 SCXI-1125 User Manual C CC e l s i u s CE Conformité Européenne— The European emissions co ntrol standard. The CE mark certifies tha t a product compli es to relev ant CE re gulations. CE is a common standard for all countries in the EU (European Union). CH channel channel Pin or wire lead to wh[...]

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    Glossary SCXI-1125 User Manual G-4 ni.com D A Q Data acquisition—(1) collecting and measuring electrical signals from sensors, transducers, and test probes or fixtures and inputting them to a computer for processing; (2 ) collecting and measuring the sam e kinds of electrical signals with A/D and/or DI O boards pl ugged into a computer, and possi[...]

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    Glossary © National Instruments Corpor ation G-5 SCXI-1125 User Manual F filtering A type of signal condition ing that allows you to remov e unwanted signal components from the signal you are trying to measure. FSR full-scale range G gain The f actor b y which a sign al is amplif ied, sometimes e xpressed in decibels. gain accurac y A measure of d[...]

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    Glossary SCXI-1125 User Manual G-6 ni.com isolation A type of si gnal conditioning in which you isolat e the transducer signals from the computer for safety purposes. Isolating the signals p rotects you and your computer from large vo ltage spik es and make s sure the measurements from th e D A Q device are not af fected by differences in ground po[...]

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    Glossary © National Instruments Corpor ation G-7 SCXI-1125 User Manual multiplexed mode An SCXI operating mode in which analog input channels are multiple xed into one module output so that yo ur cabled D A Q device has access to the module’ s multiplex ed output as well as the o utputs on all other multi plex ed modules in the chassi s through [...]

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    Glossary SCXI-1125 User Manual G-8 ni.com ppm parts per milli on PXI A rugged, open system for modular instrumentat ion based on CompactPCI, with special mechanical , electrical, and software features. The PXIbus standard was originally dev eloped by National Instruments i n 1997, and is now managed by the PXIbus Systems Alliance. R resolution The [...]

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    Glossary © National Instruments Corpor ation G-9 SCXI-1125 User Manual SCXI Signal Conditioning eX tensions for Instrumen tation—the National Instruments pr oduct line for conditioni ng low-le vel signals within an external chassis near sensors so only high-lev el signals are sent to D A Q boards in the noisy PC en vironment. SCXIbus The analog [...]

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    Glossary SCXI-1125 User Manual G-10 ni.com T thermocouple A temperature se nsor created by joining tw o dissimilar metals. The junction produces a small voltage as a function of the temperature. typ typical U UL Underwriters L aboratory V Vv o l t s VDC v olts direct current VI virtual instrument—(1) a combination of hardware and/or software elem[...]

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    © National Instruments Corpor ation I-1 SCXI-1125 User Manual Index A A C and DC voltage connections, 2-1 A C-coupling, 2-4 floating A C-coupled signal connection (figure), 2-4 floating signal, 2-3 floating signal connecti on (figure), 2-3 front signal connector figure, 2-6 table, 2-6 ground-referenced A C-coupled signal connection (figure), 2-4 g[...]

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    Index SCXI-1125 User Manual I-2 ni.com digital lines, unavailability on D A Q de vice, D-2 digital signals on SCXI-1125 (tab le), D-3 documentation con v entions used in the manual, iv E electromagnetic compatibility specifications, A-9 en vironmental specif ications, A-8 F filter setting, changing, D-4 fil t e rs bandwidth configuration, 3-1, 4-2 [...]

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    Index © National Instruments Corpor ation I-3 SCXI-1125 User Manual theory of multiplexed hardware operation, 4-3 using software for scanning operations LabVIEW and SCXI channel string, 5-25 LabVIEW and virtual chan nel string, 5-26 multiplex ed mode operation connecting t o SCXI-1125 for D A Q de vice in PXI combination, 1-4, 3-2 in SCXI chassis,[...]

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    Index SCXI-1125 User Manual I-4 ni.com front connector pin assignme nts (table), 2-6 ov ervie w, 2-1 temperature sensor connection, 2-7 software multiplexed scanning operations, 5-24 LabVIEW and SCXI channel string, 5-25 LabVIEW and virtual chan nel string, 5-26 parallel scanning operations C and parallel mode, 5-29 LabVIEW and parallel mode, 5-28 [...]