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PXIe-4480/4481 User Manual

IEPE Excitation

The PXIe-4480 provides an integrated electronic piezoelectric (IEPE) excitation current for 
each channel to measure IEPE or other current-excited sensors. To match a variety of sensor 
requirements, the current source is configurable with three settings: 4 mA, 10 mA, and 20 mA.

For maximum flexibility, the module’s IEPE current selection is programmable on a per-channel
basis.

Note

Typical IEPE sensors have an enclosure that is electrically isolated from the 

IEPE electronics. As a result, connecting the sensor to the PXIe-4480 results in a 
floating connection even though the enclosure of the sensor is grounded.

Transducer Electronic Data Sheet

The PXIe-4480 supports Class 1 Transducer Electronic Data Sheet (TEDS) according to the
IEEE 1451.4 standard.

TEDS-capable sensors carry a built-in, self-identification EEPROM that stores a table of 
parameters and sensor information. TEDS sensors have two modes of operation:

Analog mode

 allows the sensors to operate as transducers measuring physical phenomena.

Digital mode

 allows you to write and read information to and from the TEDS.

TEDS contains information about the sensor, such as calibration, sensitivity, and manufacturer 
information. This information is accessible in Measurement & Automation Explorer (MAX), 
VIs in LabVIEW, or by calling the equivalent function calls in a text-based ADE.

For more information on TEDS structure and contents, go to 

ni.com/info

 and enter the Info 

Code 

rdted6

.

Voltage Excitation

The PXIe-4480 provides a programmable voltage excitation source for each channel, designed 
primarily to interface with powered/amplified sensors. This type of sensor accepts a 
wide-ranging external power source, regulates it to a voltage suitable for its internal electronics, 
and provides its signal on amplifier output terminals.

Note

The voltage excitation feature is available only when using an accessory, such 

as the SHB12X-6RJ50, that provides access to the excitation terminals.

Содержание PXIe-4480

Страница 1: ...Dynamic Signal Acquisition PXIe 4480 4481 User Manual 6 Channel 24 bit 1 25 MS s DSA Analog Input PXIe 4480 4481 User Manual October 2016 376368A 01...

Страница 2: ...support phone numbers email addresses and current events National Instruments Corporate Headquarters 11500 North Mopac Expressway Austin Texas 78759 3504 USA Tel 512 683 0100 For further support infor...

Страница 3: ...TLE OR NON INFRINGEMENT AND ANY WARRANTIES THAT MAY ARISE FROM USAGE OF TRADE OR COURSE OF DEALING NI DOES NOT WARRANT GUARANTEE OR MAKE ANY REPRESENTATIONS REGARDING THE USE OF OR THE RESULTS OF THE...

Страница 4: ...ependent from NI and have no agency partnership or joint venture relationship with NI Patents For patents covering NI products technology refer to the appropriate location Help Patents in your softwar...

Страница 5: ...nsducer Electronic Data Sheet 2 11 Voltage Excitation 2 11 Fault Conditions 2 13 IEPE Open and IEPE Short 2 13 Voltage Excitation Current Limit 2 13 Overtemperature Detection 2 14 Chapter 3 Signal Acq...

Страница 6: ...Mode 3 8 Data Throughput 3 9 Timing and Triggering 3 10 Sample Clock Timebase 3 10 External Clock 3 10 Timing Engines 3 11 Digital Triggering 3 11 Analog Triggering 3 11 Triggering and Filter Delay 3...

Страница 7: ...on and harshness NVH measurements High speed blast and pressure events Underwater transient acoustic measurements The PXIe 4480 offers a large set of sensor conditioning features including charge meas...

Страница 8: ...cessories Accessories for the PXIe 4480 and PXIe 4481 include the following shielded InfiniBand 12x cables SHB12X 6BNC 6 BNC analog inputs SHB12X 6MXLRM 6 mini XLR analog inputs SHB12X 6RJ50 6 RJ50 an...

Страница 9: ...I 0 5 G1 G2 G3 G4 G5 G6 G7 G8 G9 G10 G11 G12 G13 G14 G15 G16 G17 G18 G19 G20 G21 G22 G23 G24 G25 AI 0 AI 0 AI 1 AI 1 AI 2 AI 2 AI 3 AI 3 AI 4 AI 4 AI 5 AI 5 S1 S3 S5 S7 S9 S11 S13 S15 S17 S19 S21 S23...

Страница 10: ...to 5 AI 0 5 G1 G2 G3 G4 G5 G6 G7 G8 G9 G10 G11 G12 G13 G14 G15 G16 G17 G18 G19 G20 G21 G22 G23 G24 G25 AI 0 AI 0 AI 1 AI 1 AI 2 AI 2 AI 3 AI 3 AI 4 AI 4 AI 5 AI 5 S1 S3 S5 S7 S9 S11 S13 S15 S17 S19 S2...

Страница 11: ...ESERVED Reserved for accessories or other use Table 2 2 RJ50 Connector Pin Assignments RJ50 Modular Plug Pin Number Diagram Pin Signal Name Signal Description 1 NC No connect 2 AI Positive analog inpu...

Страница 12: ...ption 1 AI Positive analog input signal 0 to 5 2 AI Negative analog input signal 0 to 5 Table 2 4 mXLR Connector Pin Assignments mXLR Male Connector Pin Diagram Pin Signal Name Signal Description 1 GN...

Страница 13: ...ber The module is being accessed The Access LED flashes amber for 75 ms when the module is accessed Green Module is ready to be accessed by software Active Off Module is not acquiring or preparing to...

Страница 14: ...nalog Input Block Diagram Filter Select Charge Amplifier Lowpass Filter Charge Out Charge In Excitation Voltage 10 V 25 V Adj 9 5 V to 12 V EX 0 5 GND EX 0 5 Voltage Charge Voltage Charge 4mA 10mA 20m...

Страница 15: ...lock diagram Depending on the connector type connect the signals as described in the Connecting Signals section Figure 2 4 PXIe 4481 Analog Input Block Diagram AI 0 5 AI 0 5 1 62 M ADC 1 62 M 50 AC DC...

Страница 16: ...gnal source is floating use the pseudodifferential input configuration The pseudodifferential configuration provides a ground reference connection for the floating source by connecting a 50 resistor f...

Страница 17: ...setup Configure the channels based on the signal source reference or DUT configuration Refer to Table 2 7 to determine how to configure the channel For maximum flexibility the module s input configura...

Страница 18: ...oupling any DC offset present in the source signal is passed to the ADC The DC coupled configuration is usually best if the signal source has only small amounts of offset voltage or if the DC content...

Страница 19: ...able of parameters and sensor information TEDS sensors have two modes of operation Analog mode allows the sensors to operate as transducers measuring physical phenomena Digital mode allows you to writ...

Страница 20: ...V It is also possible to utilize the voltage excitation source to excite a passive full bridge strain gage as shown in Figure 2 9 Refer to Table 2 8 for a guide to connecting signals from the PXIe 448...

Страница 21: ...the attached signal source Common connection issues that can occur include open and short circuits An open circuit occurs if there is a disconnect between the signal source and the module resulting i...

Страница 22: ...ing acquired may be compromised while the PXIe 4480 4481 is displaying an overtemperature condition If an overtemperature condition is detected the hardware will turn the Active LED red and set a flag...

Страница 23: ...ta is decimated to the requested user sample rate and digital filters are applied to filter out frequency content above the Nyquist frequency Frequency domain mode is used any time the requested sampl...

Страница 24: ...ng frequency components above the Nyquist limit The undesirable effect of the digitizer modulating out of band components into the Nyquist bandwidth is aliasing The greatest danger of aliasing is that...

Страница 25: ...with that event is available at the output of the acquisition and filtering process This delay is called the group delay In order to simplify the process of acquiring data from the PXIe 4480 4481 modu...

Страница 26: ...passed through the same analog front end circuitry as in a frequency domain mode acquisition This means that time domain mode can use all of the same analog channel configurations available on the PXI...

Страница 27: ...e program it to the PXIe 4480 4481 It is required that the filter have the following characteristics Have between 1 and 36 coefficients Filters larger than 36 coefficients are not allowed due to hardw...

Страница 28: ...modulator noise Refer to the PXIe 4480 4481 Specifications for more information about the default filter and the performance of time domain mode when using the default filter Step response is affecte...

Страница 29: ...sample rate than 20 MS s When hardware decimates it does so by returning every nth sample coming out of the filter For example to produce a sample rate of 5 MS s n 4 the hardware drops the first thre...

Страница 30: ...al FIR filter always operates at 20 MS s regardless of the final rate returned to the user after decimation Therefore it is possible for aliasing to occur when using the lower sample rates supported b...

Страница 31: ...is transferred for every sample To improve efficiency the PXIe 4480 4481 supports packing the sample data so that this unused byte is eliminated This can be controlled by setting NI DAQmx Channel Pro...

Страница 32: ...idth for example at least 500 MB s slot bandwidth and a sufficient system bandwidth to operate all devices installed in the system If a PXI Express remote controller is selected it should use a x4 or...

Страница 33: ...n a reference triggered acquisition you configure the module to acquire a certain number of pre trigger samples and a certain number of post trigger samples Reference triggered acquisitions can theref...

Страница 34: ...eases as sample rates decrease Synchronization Some applications require tight synchronization between input and output operations on multiple modules Synchronization is important to minimize skew bet...

Страница 35: ...d Synchronization Synchronization Type to Slave and that of the Master to Master 7 Query DAQmx Timing More Synchronization Pulse Synchronization Time on all modules being synchronized choose the maxim...

Страница 36: ...y your systems accuracy and reliability requirements and provides warranty sparing and calibration services to help you maintain accuracy and minimize downtime over the life of your system Visit ni co...

Страница 37: ...tions Engineers make sure every question submitted online receives an answer Software Support Service Membership The Standard Service Program SSP is a renewable one year subscription included with alm...

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