National Instruments Isolated Analog Input Device NI PXI-4224 User Manual
Summary of Isolated Analog Input Device NI PXI-4224
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Pxi ni pxi-4224 user manual ni pxi-4224 user manual august 2008 373752g-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 3...
Page 3: Important Information
Important information warranty the ni pxi-4224 is warranted against defects in materials and workmanship for a period of one year from the date of shipment, as evidenced by receipts or other documentation. National instruments will, at its option, repair or replace equipment that proves to be defect...
Page 4: Conventions
Conventions the following conventions are used in this manual: angle brackets that contain numbers separated by an ellipsis represent a range of values associated with a bit or signal name—for example, ao . » the » symbol leads you through nested menu items and dialog box options to a final action. ...
Page 5: Contents
© national instruments corporation v ni pxi-4224 user manual contents chapter 1 about the ni pxi-4224 what you need to get started ......................................................................................1-2 national instruments documentation ...............................................
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Contents ni pxi-4224 user manual vi ni.Com chapter 5 using the ni pxi-4224 developing your application ....................................................................................... 5-1 typical program flow chart........................................................................... 5-1...
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Contents © national instruments corporation vii ni pxi-4224 user manual figures figure 2-1. Ni pxi-4224 front label ......................................................................2-3 figure 2-2. Unshielded floating signal source connection using a d-sub connector ................................
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Contents ni pxi-4224 user manual viii ni.Com tables table 2-1. Ni pxi-4224 25-pin d-sub terminal pin assignments ..................... 2-2 table 4-1. Signal conditioning functional blocks ................................................ 4-3 table 4-2. Pxi trigger bus timing signals ....................
Page 9: About The Ni Pxi-4224
© national instruments corporation 1-1 ni pxi-4224 user manual 1 about the ni pxi-4224 this chapter provides an introduction to the ni pxi-4224 device and its installation. The ni pxi-4224 is part of the ni pxi-4200 series of data acquisition (daq) devices with integrated signal conditioning. The px...
Page 10: What You Need to Get Started
Chapter 1 about the ni pxi-4224 ni pxi-4224 user manual 1-2 ni.Com what you need to get started to set up and use the ni pxi-4224, you need the following: ❑ hardware – ni pxi-4224 – one of the following: • tb-2725 terminal block • 25-pin d-sub female connector – pxi or pxi/scxi combination chassis ❑...
Page 11: And The Daq Device
Chapter 1 about the ni pxi-4224 © national instruments corporation 1-3 ni pxi-4224 user manual national instruments documentation the ni pxi-4224 user manual is one piece of the documentation set for your daq system. You could have any of several types of manuals depending on the hardware and softwa...
Page 12: Installing The Ni Pxi-4224
Chapter 1 about the ni pxi-4224 ni pxi-4224 user manual 1-4 ni.Com installing the ni pxi-4224 note refer to the read me first: radio-frequency interference document before removing equipment covers or connecting or disconnecting any signal wires. Refer to the daq getting started guide to unpack, ins...
Page 13: Connecting Signals
© national instruments corporation 2-1 ni pxi-4224 user manual 2 connecting signals this chapter provides details about the front signal connector of the ni pxi-4224 and how to connect signals to the ni pxi-4224. Connecting signals to the ni pxi-4224 after you have verified that the ni pxi-4224 is i...
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Chapter 2 connecting signals ni pxi-4224 user manual 2-2 ni.Com caution the pfi 0/cal smb connector is for low-voltage timing and calibration signals only . Voltages greater than ±15 v can damage the device. If you are building a 25-pin d-sub connector for your application, make sure you use a conne...
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Chapter 2 connecting signals © national instruments corporation 2-3 ni pxi-4224 user manual figure 2-1. Ni pxi-4224 front label analog input connections the following sections provide a definition of the signal source characteristics, descriptions of various ways to connect signals to the ni pxi-422...
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Chapter 2 connecting signals ni pxi-4224 user manual 2-4 ni.Com in the electrical diagrams, two different ground symbols are used. These symbols indicate that you cannot assume that the indicated grounds are at the same potential. Refer to appendix a, specifications , for maximum working voltage spe...
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Chapter 2 connecting signals © national instruments corporation 2-5 ni pxi-4224 user manual figure 2-3. Unshielded grounded signal source connection using a d-sub connector ch 0 ch 7 + – twi s ted-p a ir wiring v s ig v s ig ground reference s ign a l s ource ai 0 + ai 0 – ai 7 + ai 7 –.
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Chapter 2 connecting signals ni pxi-4224 user manual 2-6 ni.Com figure 2-4. Shielded floating signal source connection using a d-sub connector + – ai 0 + ai 0 – ch 0 v s ig s ign a l s ource ai 7 + ai 7 – ch 7 s hielding twi s ted-p a ir wiring.
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Chapter 2 connecting signals © national instruments corporation 2-7 ni pxi-4224 user manual figure 2-5. Shielded grounded signal source connection using a d-sub connector ch 0 ch 7 s hielding + – twi s ted-p a ir wiring v s ig v s ig ground reference s ign a l s ource ai 0 + ai 0 – ai 7 + ai 7 –.
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Chapter 2 connecting signals ni pxi-4224 user manual 2-8 ni.Com figures 2-6 through 2-9 illustrate connecting signals using a terminal block. Figure 2-6. Unshielded floating signal source connection using a terminal block + – twi s ted-p a ir wiring ai 0 + ai 0 – ch 0 v s ig s ign a l s ource termin...
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Chapter 2 connecting signals © national instruments corporation 2-9 ni pxi-4224 user manual figure 2-7. Unshielded grounded signal source connection using a terminal block twi s ted-p a ir wiring ai 0 + ai 0 – ch 0 ai 7 + ai 7 – ch 7 + – v s ig v s ig ground reference s ign a l s ource termin a l bl...
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Chapter 2 connecting signals ni pxi-4224 user manual 2-10 ni.Com figure 2-8. Shielded floating signal source connection using a terminal block + – twi s ted-p a ir wiring ai 0 + ai 0 – ch 0 v s ig s ign a l s ource termin a l block ai 7 + ai 7 – ch 7 s hielding.
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Chapter 2 connecting signals © national instruments corporation 2-11 ni pxi-4224 user manual figure 2-9. Shielded grounded signal source connection using a terminal block floating signal source connection figures 2-2, 2-4, 2-6, and 2-8 illustrate floating signal source connections. In this configura...
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Chapter 2 connecting signals ni pxi-4224 user manual 2-12 ni.Com ground-referenced signal connection figures 2-3, 2-5, 2-7, and 2-9 illustrate the ground-referenced signal connection. In this configuration, the voltage source being measured is referenced to its own ground reference that is connected...
Page 25: Configuring and Testing
© national instruments corporation 3-1 ni pxi-4224 user manual 3 configuring and testing this chapter provides details about configuring and testing the ni pxi-4224 in max, including how to use device test panels and create and configure ni-daqmx tasks and ni-daqmx global channels. Verifying and sel...
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Chapter 3 configuring and testing ni pxi-4224 user manual 3-2 ni.Com configuring the ni pxi-4224 in max this section describes how to create ni-daqmx tasks and ni-daqmx global channels in max that allow you to take measurements with the ni pxi-4224. Creating a voltage task or global channel using ni...
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Chapter 3 configuring and testing © national instruments corporation 3-3 ni pxi-4224 user manual verifying and self-testing an ni-daqmx task or global channel after you have created an analog input voltage ni-daqmx task or ni-daqmx global channel, verify the ni-daqmx task or ni-daqmx global channel ...
Page 28: Theory of Operation
© national instruments corporation 4-1 ni pxi-4224 user manual 4 theory of operation this chapter describes the theory of operation, measurement considerations, and timing information. Theory of operation figure 4-1 illustrates the key functional components of the ni pxi-4224, including the daq and ...
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Chapter 4 theory of operation ni pxi-4224 user manual 4-2 ni.Com figure 4-1. Block diagram of ni pxi-4224 ni-pga input protection ai0 input protection ai1 input protection ai2 input protection ai3 input protection ai4 input protection ai5 input protection ai6 input protection ai7 pga po s t filter i...
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Chapter 4 theory of operation © national instruments corporation 4-3 ni pxi-4224 user manual signal conditioning functional overview the ni pxi-4224 is part of the pxi-4200 series of daq devices with integrated signal conditioning designed to provide application-specific signal conditioning, daq, an...
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Chapter 4 theory of operation ni pxi-4224 user manual 4-4 ni.Com figure 4-2. Effect of input impedance on signal measurements although r s does not influence dc measurements, take care when measuring ac signals since c in attenuates higher frequencies if r s is too large. For example: common-mode re...
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Chapter 4 theory of operation © national instruments corporation 4-5 ni pxi-4224 user manual effective cmr when the frequency of a common-mode signal is known and outside of the measurement frequency band of interest, you can use an analog or digital filter, or both, to further reduce the residual e...
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Chapter 4 theory of operation ni pxi-4224 user manual 4-6 ni.Com figure 4-3. Ai conv clk signal routing figure 4-3 shows that ai conv clk can be generated from a number of sources, such as the external signals pfi 0, pxi_trig, and pxi_star, and the ctr 0 internal output. Programmable function inputs...
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Chapter 4 theory of operation © national instruments corporation 4-7 ni pxi-4224 user manual device and pxi clocks many functions performed by the ni pxi-4224 require a frequency timebase to generate the necessary timing signals for controlling a/d conversions, digital-to-analog converter (dac) upda...
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Chapter 4 theory of operation ni pxi-4224 user manual 4-8 ni.Com figure 4-4 shows this signal connection scheme. Figure 4-4. Ni pxi-4224 pxi trigger bus signal connection pxi bu s connector s witch rt s i s witch pxi trigger pxi trigger daq- s tc ai s tart trig ai ref trig ai conv clk ai s amp clk a...
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Chapter 4 theory of operation © national instruments corporation 4-9 ni pxi-4224 user manual table 4-2 provides more information about each of the timing signals available on the pxi trigger bus. For more detailed timing signal information, refer to appendix b, timing signal information . Table 4-2....
Page 37: Using The Ni Pxi-4224
© national instruments corporation 5-1 ni pxi-4224 user manual 5 using the ni pxi-4224 this chapter describes how to program the ni pxi-4224, using daq assistant or labview, and how to calibrate the device. Developing your application this section describes the software and programming steps necessa...
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Chapter 5 using the ni pxi-4224 ni pxi-4224 user manual 5-2 ni.Com figure 5-1. Typical program flowchart no no no no no no configure ch a nnel s re a d me as urement adju s t timing s etting s s top me as urement cre a te t as k u s ing daq a ss i s t a nt? Ye s ye s ye s ye s ye s ye s cre a te t a...
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Chapter 5 using the ni pxi-4224 © national instruments corporation 5-3 ni pxi-4224 user manual overview of typical flow chart the following sections briefly discuss some considerations for some of the steps in figure 5-1. These sections are meant to provide an overview of some of the options and fea...
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Chapter 5 using the ni pxi-4224 ni pxi-4224 user manual 5-4 ni.Com when programmatically adjusting timing settings, you can set the task to acquire continuously, acquire a buffer of samples, or acquire one point at a time. For continuous and buffered acquisitions, you can set the acquisition rate an...
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Chapter 5 using the ni pxi-4224 © national instruments corporation 5-5 ni pxi-4224 user manual acquiring, analyzing, and presenting after configuring the task and channels, you can start your acquisition, read measurements, analyze the data returned, and display it according to the needs of your app...
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Chapter 5 using the ni pxi-4224 ni pxi-4224 user manual 5-6 ni.Com table 5-2. Programming a task in labview flowchart step vi or program step create task in daq assistant create a daqmx task name constant located on the controls»all controls»i/o»daqmx name controls subpalette, right-click it, and se...
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Chapter 5 using the ni pxi-4224 © national instruments corporation 5-7 ni pxi-4224 user manual using a daqmx channel property node in labview you can use property nodes in labview to manually configure your channels. To create a labview property node, complete the following steps: 1. Launch labview....
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Chapter 5 using the ni pxi-4224 ni pxi-4224 user manual 5-8 ni.Com 8. Once you have added the property to the property node, right-click the terminal to change the attributes of the property, or to add a control, constant, or indicator. 9. To add another property to the property node, right-click an...
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Chapter 5 using the ni pxi-4224 © national instruments corporation 5-9 ni pxi-4224 user manual figure 5-2. General synchronizing flowchart ye s no ye s no configure m as ter timing re a d me as urement cre a te a m as ter t as k (option a l) cre a te m as ter ai volt a ge ch a nnel s configure m as ...
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Chapter 5 using the ni pxi-4224 ni pxi-4224 user manual 5-10 ni.Com synchronizing the ni pxi-4224 using labview this section describes in more detail the steps shown in figure 5-2, such as how to create a task in labview and configure the channels of the ni pxi-4224. For further instructions, select...
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Chapter 5 using the ni pxi-4224 © national instruments corporation 5-11 ni pxi-4224 user manual other application documentation and material the following locations provide more information that you may find useful when setting up or connecting signal sources or programming your application. • labvi...
Page 48: Calibrating The Ni Pxi-4224
Chapter 5 using the ni pxi-4224 ni pxi-4224 user manual 5-12 ni.Com calibrating the ni pxi-4224 calibration refers to the process of minimizing measurement errors. On the ni pxi-4224, errors from the digitizer components of the daq device circuitry are corrected in the analog circuitry by onboard ca...
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Chapter 5 using the ni pxi-4224 © national instruments corporation 5-13 ni pxi-4224 user manual 4. Right-click the ni pxi-4224 and select self-calibrate . 5. A dialog box opens indicating that the ni pxi-4224 is self-calibrating. 6. When the dialog box closes, the ni pxi-4224 is successfully self-ca...
Page 50: Specifications
© national instruments corporation a-1 ni pxi-4224 user manual a specifications this appendix lists the specifications for the ni pxi-4224 device. These specifications are typical at 25 °c unless otherwise noted. Overvoltage protection powered on or off................................... 42.4 v peak...
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Appendix a specifications for ni pxi-4224 user manual a-2 ni.Com input coupling.........................................Dc bandwidth, –3 db ...................................15 khz slew rate .................................................2 v/ μ s typical input impedance powered on ..................
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Appendix a specifications for © national instruments corporation a-3 ni pxi-4224 user manual calibration recommended warm-up time ................ 30 minutes external calibration interval................... 1 year pre-calibration errors 1 pre-calibration offset error relative to input (rti) ...........
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Appendix a specifications for ni pxi-4224 user manual a-4 ni.Com response .................................................Rising or falling edge, software programmable pulse width .............................................10 ns min impedance...............................................10 k Ω c...
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Appendix a specifications for © national instruments corporation a-5 ni pxi-4224 user manual weight .................................................... 279 g (9.8 oz) analog input signal connector ............... 25-pin d-sub maximum working voltage (signal + common-mode) each input should remain w...
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Appendix a specifications for ni pxi-4224 user manual a-6 ni.Com safety this product meets the requirements of the following standards of safety for electrical equipment for measurement, control, and laboratory use: • iec 61010-1, en 61010-1 • ul 61010-1, csa 61010-1 note for ul and other safety cer...
Page 56: Rohs
Appendix a specifications for © national instruments corporation a-7 ni pxi-4224 user manual environmental management ni is committed to designing and manufacturing products in an environmentally responsible manner. Ni recognizes that eliminating certain hazardous substances from our products is ben...
Page 57: Timing Signal Information
© national instruments corporation b-1 ni pxi-4224 user manual b timing signal information this appendix contains additional information about the timing signals discussed in chapter 4, theory of operation . Connecting timing signals caution exceeding the maximum input voltage ratings listed in appe...
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Appendix b timing signal information ni pxi-4224 user manual b-2 ni.Com daq timing connections the timing signals are ai start trig, ai ref trig, ai samp clk, ai conv clk, ai pause trig, ai sample clk timebase, and ai hold complete. Posttriggered daq allows you to view data that is acquired after a ...
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Appendix b timing signal information © national instruments corporation b-3 ni pxi-4224 user manual ai start trig signal the ai start trig signal can be input or output through pfi 0, pxi_trig, or pxi_star. As an input, ai start trig is configured in the edge-detection mode. You can select pfi 0 as ...
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Appendix b timing signal information ni pxi-4224 user manual b-4 ni.Com the device also uses ai start trig to initiate pretriggered operations. In pretriggered applications, ai start trig is generated by a software trigger unless a pfi pin is selected as the source of ai start trig. Refer to the ai ...
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Appendix b timing signal information © national instruments corporation b-5 ni pxi-4224 user manual figure b-6. Ai ref trig output signal timing ai samp clk signal the ai samp clk signal can be externally input from pfi 0, pxi_trig, or pxi_star. It can be output on any pxi trigger bus line. Refer to...
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Appendix b timing signal information ni pxi-4224 user manual b-6 ni.Com figures b-7 and b-8 show the input and output timing requirements for ai samp clk. Figure b-7. Ai samp clk input signal timing figure b-8. Ai samp clk output signal timing the ai conv clk pulses are masked off until the device g...
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Appendix b timing signal information © national instruments corporation b-7 ni pxi-4224 user manual ai samp clk generates a conversion. Separate the ai samp clk pulses by at least one scan period. A counter on the device internally generates ai samp clk unless you select some external source. The ai...
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Appendix b timing signal information ni pxi-4224 user manual b-8 ni.Com figure b-10. Ai conv clk output signal timing the adc switches to hold mode within 60 ns of the selected edge. This hold-mode delay time is a function of temperature and does not vary from one conversion to the next. Separate th...
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Appendix b timing signal information © national instruments corporation b-9 ni pxi-4224 user manual ai sample clk timebase signal pfi 0, pxi_trig, or pxi_star can externally input the ai sample clk timebase signal, which is not available as an output on the i/o connector. The onboard scan interval (...
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Appendix b timing signal information ni pxi-4224 user manual b-10 ni.Com ai hold complete signal ai hold complete is an output-only signal that generates a pulse with the leading edge occurring approximately 50 to 100 ns after an a/d conversion begins. The polarity of this output is software configu...
Page 67: Removing The Ni Pxi-4224
© national instruments corporation c-1 ni pxi-4224 user manual c removing the ni pxi-4224 this appendix provides details for removing an ni pxi-4224 device from max and from a pxi or pxi/scxi combination chassis. Note you must physically remove the ni pxi-4224 from the chassis before you can remove ...
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Appendix c removing the ni pxi-4224 ni pxi-4224 user manual c-2 ni.Com figure c-1. Injector/ejector handle position before device removal removing the ni pxi-4224 from max to remove an ni pxi-4224 device from max, complete the following steps after launching max: 1. Expand devices and interfaces to ...
Page 69: Common Questions
© national instruments corporation d-1 ni pxi-4224 user manual d common questions this appendix lists common questions related to the use of the ni pxi-4224. Which version of ni-daq works with the ni pxi-4224 and how do i get the most current version of ni-daq? You must have ni-daq 7.3.1 or later an...
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Appendix d common questions ni pxi-4224 user manual d-2 ni.Com how do i perform an external calibration of the ni pxi-4224? As of the ni pxi-4224 release, an external calibration document is not available. To check the availability of an ni pxi-4224 external calibration document is go to ni.Com/cali...
Page 71: Glossary
© national instruments corporation g-1 ni pxi-4224 user manual glossary symbol prefix value p pico 10 –12 n nano 10 –9 μ micro 10 – 6 m milli 10 –3 k kilo 10 3 m mega 10 6 g giga 10 9 t tera 10 12 symbols / per. ° degree. % percent. + positive of, or plus. – negative of, or minus. Ω ohm. A a amperes...
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Glossary ni pxi-4224 user manual g-2 ni.Com adc analog-to-digital converter—an electronic device, often an integrated circuit, that converts an analog voltage to a digital number. Ade application development environment. Ai analog input. Ai conv clk convert signal. Ai hold complete scan clock signal...
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Glossary © national instruments corporation g-3 ni pxi-4224 user manual cmr common-mode rejection. Cmrr common-mode rejection ratio—a measure of an instrument’s ability to reject interference from a common-mode signal, usually expressed in decibels (db). Common-mode signal any voltage present at the...
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Glossary ni pxi-4224 user manual g-4 ni.Com dma direct memory access—a method by which data can be transferred to/from computer memory from/to a device or memory on the bus while the processor does something else. Dma is the fastest method of transferring data to/from computer memory. Dnl differenti...
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Glossary © national instruments corporation g-5 ni pxi-4224 user manual h h hour or hours. Hz hertz—the number of scans read or updates written per second. I i/o input/output—the transfer of data to/from a computer system involving communications channels, operator interface devices, and/or daq and ...
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Glossary ni pxi-4224 user manual g-6 ni.Com l labview laboratory virtual instrument engineering workbench—a program development application based on the programming language g and used commonly for test and measurement purposes. Led light-emitting diode. Linearity the adherence of device response to...
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Glossary © national instruments corporation g-7 ni pxi-4224 user manual n ni-daqmx the latest ni-daq driver with new vis, functions, and development tools for controlling measurement devices. Noise an undesirable electrical signal—noise comes from external sources such as the ac power line, motors, ...
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Glossary ni pxi-4224 user manual g-8 ni.Com r relative accuracy a measure in lsb of the accuracy of an adc. It includes all nonlinearity and quantization errors. It does not include offset and gain errors of the circuitry feeding the adc. Resolution the smallest signal increment that can be detected...
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Glossary © national instruments corporation g-9 ni pxi-4224 user manual scxi signal conditioning extensions for instrumentation—the ni product line for conditioning low-level signals within an external chassis near sensors so only high-level signals are sent to daq devices in the noisy pc environmen...
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Glossary ni pxi-4224 user manual g-10 ni.Com w waveform multiple voltage readings taken at a specific sampling rate. Working voltage the highest voltage with respect to ground that should be applied to an input terminal during normal use, normally well under the breakdown voltage for safety margin. ...
Page 81: Index
© national instruments corporation i-1 ni pxi-4224 user manual index a ai conv clk signal input signal timing (figure), b-7 output signal timing (figure), b-8 overview, b-7 signal routing (figure), 4-6 ai hold complete signal description (table), 4-9 overview, b-10 signal timing (figure), b-10 ai pa...
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Index ni pxi-4224 user manual i-2 ni.Com pre-calibration errors, a-3 self-calibration, 5-12 specifications, a-3 ce compliance specifications, a-6 channel properties, configuring in application development (table), 5-4 in labview, 5-7 clocks, pxi, 4-7 see also daq timing connections see also pxi trig...
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Index © national instruments corporation i-3 ni pxi-4224 user manual f floating signal source connection connecting to ni pxi-4224, 2-11 front signal connector, 2-1 front label of ni pxi-4224 (figure), 2-3 signal assignments of ni pxi-4224 (table), 2-2 g global channel creating, 3-2 verifying, 3-3 g...
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Index ni pxi-4224 user manual i-4 ni.Com signal conditioning overview, 4-3 timing and control overview, 4-5 ni-daq software, 1-3, d-1 ni-daqmx channel properties, configuring (table), 5-4 ni-daqmx global channel creating, 3-2 verifying and self-testing, 3-3 ni-daqmx task creating, 3-2 verifying and ...
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Index © national instruments corporation i-5 ni pxi-4224 user manual specifications analog input, a-1 calibration, a-3 ce compliance, a-6 digital triggers, a-3 electromagnetic compatibility, a-6 environmental, a-5 maximum working voltage, a-5 memory, a-3 overvoltage protection, a-1 pci bus interface...