National instruments high-speed can module operating instructions (29 pages)
Summary of Contents for National Instruments NI 9235
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OPERATING INSTRUCTIONS AND SPECIFICATIONS NI 9235/9236 8-Channel, 24-Bit Quarter-Bridge Analog Input Module Français Deutsch ni.com/manuals...
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This document describes how to use the National Instruments 9235 and National Instruments 9236 and includes specifications and terminal assignments. In this document, the NI 9235 and NI 9236 are referred to inclusively as the NI 9235/9236. Visit and enter ni.com/info...
Touching this component may result in bodily injury. Safety Guidelines for Hazardous Locations The NI 9235/9236 is suitable for use in Class I, Division 2, Groups A, B, C, D, T4 hazardous locations; Class I, Zone 2, AEx nA IIC T4, and Ex nA IIC T4 hazardous locations; and nonhazardous locations only.
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II 3G and is suitable for use in Zone 2 hazardous locations. If you are using the NI 9235/9236 in Gas Group IIC hazardous locations or in ambient temperatures of –40 °C ≤ Ta ≤ 70 °C, you must use the device in an NI chassis that has been evaluated as EEx nC IIC T4, Ex nA IIC T4, or Ex nL IIC T4 equipment.
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Connecting the NI 9235/9236 The NI 9235/9236 has a 24-terminal detachable spring-terminal connector that provides connections for 8 analog input channels. Figure 1. NI 9235/9236 Terminal Assignments NI 9235/9236 ni.com...
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Refer to the Specifications section for more information about spring-terminal wiring. Figure 3. Connecting Wires to the NI 9235/9236 Connector NI 9235/9236 ni.com...
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Wiring for High-Vibration Applications If an application is subject to high vibration, National Instruments recommends that you use the NI 9965 backshell kit to protect the connections. Refer to Figure 4 for an illustration of the NI 9965 connector backshell.
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You must connect each EXC terminal to only one gage to maintain the channel-to-channel crosstalk performance of the module. Each channel on the NI 9235/9236 has an independent 24-bit ADC and input amplifier that enables you to sample signals from all eight channels simultaneously.
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NI 9236 Figure 6. Input Circuitry for One Channel of the NI 9236 The NI 9235/9236 also includes filters to prevent aliasing. The filters on the NI 9235/9236 filter according to the sampling rate. Refer to the Understanding NI 9235/9236 Filtering section for more information about filtering.
Refer to the software help for information about enabling the shunt calibration switch for the NI 9235/9236. Each input channel has a unique shunt calibration resistor that can operate independently, as shown in Figures 5 and 6.
Excitation Voltage The NI 9235/9236 provides a constant excitation supply voltage to each channel. The excitation supply provides sufficient output current to power all eight channels at minimum resistance. The excitation supply retains regulation even if one channel experiences a gage short.
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The small amount of variation in gain with respect to frequency is called the passband flatness. The digital filters of the NI 9235/9236 adjust the frequency range of the passband to match the data rate. Therefore, the amount of gain or attenuation at a given frequency depends on the data rate.
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0.025 0.000 –0.025 –0.050 Figure 7. Typical Passband Response for the NI 9235/9236 NI 9235/9236 Frequency (kHz) ni.com...
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Alias-Free Bandwidth Any signal that appears in the alias-free bandwidth of the NI 9235/9236 is not an aliased artifact of signals at a higher frequency. The alias-free bandwidth is defined by the ability of the filter to reject frequencies above the stopband frequency and equals the data rate minus the stopband frequency.
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7.143 kS/s, and so on down to 794 S/s, depending on the value of n. When using an external timebase with a frequency other than 12.8 MHz, the NI 9235/9236 has a different set of data rates. The cRIO-9151 R Series Expansion chassis does Note not support sharing timebases between modules.
The following specifications are typical for the range –40 to 70 °C unless otherwise noted. The specifications are the same for the NI 9235 and the NI 9236 unless otherwise noted. Input Characteristics Number of channels... 8 analog input channels Quarter-bridge completion NI 9235...
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Accuracy, NI 9235 Measurement Conditions Calibrated typ (25 °C, ±5 °C) Calibrated max (–40 to 70 °C) Uncalibrated typ (25 °C, ±5 °C) Uncalibrated max (–40 to 70 °C) Exclusive of lead wire desensitization error. † Range equals 29.4 mV/V.
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= 0 to 4 kHz... ±0.1° Input delay ... 38.2/f Passband Frequency ... 0.45 · f Flatness (f = 10 kS/s)... 33 mdB max Stopband Frequency ... 0.55 · f Rejection... 100 dB NI 9235/9236 Gain Maximum 0.11% 0.32% + 11 μs Phase Maximum ·...
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Rejection at oversample rate = 10 kS/s) ... 80 dB @ 640 kHz Input noise = 1 kS/s NI 9235 ... 0.38 μV/V NI 9236 ... 0.25 μV/V = 10 kS/s NI 9235 ... 0.85 μV/V NI 9236 ... 0.5 μV/V SFDR (1 kHz, –60 dBFS)
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= 1 kHz) ... –100 dB Common-mode voltage, all signals to earth ground... ±60 VDC CMRR (f = 0 to 60 Hz) NI 9235... 120 dB NI 9236... 110 dB MTBF ... 566,796 hours at 25 °C; Contact NI for Bellcore MTBF specifications Note at other temperatures or for MIL-HDBK-217F specifications.
Excitation Characteristics Excitation type ... Constant voltage Excitation value NI 9235... 2.0 V ± 1% NI 9236... 3.3 V ± 1% Maximum output current NI 9235... 80 mA NI 9236... 46 mA Power Requirements Power consumption from chassis NI 9235 Active mode ...
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Such voltage measurements include signal levels, special equipment, limited-energy parts of equipment, circuits powered by regulated low-voltage sources, and electronics. Do not connect the NI 9235/9236 to signals or Caution use for measurements within Measurement Categories II, III, or IV.
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Environmental National Instruments C Series modules are intended for indoor use only but may be used outdoors if installed in a suitable enclosure. Refer to the manual for the chassis you are using for more information about meeting these specifications.
Certification column. Environmental Management National Instruments is committed to designing and manufacturing products in an environmentally responsible manner. NI recognizes that eliminating certain hazardous substances from our products is beneficial not only to the environment but also to NI customers.
NI 9235/9236 at ni.com/ calibration Calibration interval ... 1 year Where to Go for Support The National Instruments Web site is your complete resource for technical support. At you have access to ni.com/support everything from troubleshooting and application development self-help resources to email and phone assistance from NI Application Engineers.
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National Instruments, NI, ni.com, and LabVIEW are trademarks of National Instruments Corporation. Refer to the Terms of Use section on ni.com/legal for more information about National Instruments trademarks. Other product and company names mentioned herein are trademarks or trade names of their respective companies.
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