Manuale d’uso / di manutenzione del prodotto NI PXI-5422 del fabbricante National Instruments
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CALIBRATION PROCEDURE NI PXI-5422 This document contains step-by-step in structions for writing a calibration procedure for the NI PXI-5422 arbitrary wa veform generator . Contents Conventions .............. .............. .............. .............
NI PXI-5422 Calibration Pr ocedure 2 ni.com Adjusting the Analog Output ................... .............. ................. ..35 Adjusting the Oscillator Frequency................... ................. .......52 Adjusting the Calibration ADC .........
© National Instruments Corporation 3 NI PXI-5422 Calibration Procedure What Is Calibration? Calibration consists of verifying the output accuracy of a device and correcting for any output error. Veri fication is measuring the performance of a device and comp aring the resul ts to the sp ecifications of the device.
NI PXI-5422 Calibration Pr ocedure 4 ni.com The output accuracy requirements of your application determine ho w often you should externally calibrate the NI PXI-5422. NI recomm ends that you perform a complete external calibra tion at least once ev ery two years.
© National Instruments Corporation 5 NI PXI-5422 Calibration Procedure calling a 32-bit DLL. Many of the functions use constants def ined in the niFgen.h f ile. T o use these constants in C, you must include niFgen.h in your code when you write the calibration procedure.
NI PXI-5422 Calibration Pr ocedure 6 ni.com Documentation For information about NI-FGEN and the NI PXI-5 422, you may find the following docum ents helpful: • NI Signal Generators Getting Started Gu.
© National Instruments Corporation 7 NI PXI-5422 Calibration Procedure 3. Select the device that you want to calibrate. 4. Initiate self-calibration in one of the following ways: •C l i c k Self-Calibrate in the upper right corner . • Right-click the de vice name under Devices and Interf aces, and select Self-Calibrate from the drop-down menu.
NI PXI-5422 Calibration Pr ocedure 8 ni.com External Calibration Options External calibration involves bo th verification and adjustment. Verification is the process of testing the device to ensure that the output accuracy is within certain speci fications.
© National Instruments Corporation 9 NI PXI-5422 Calibration Procedure Figure 1. Complete Calibration Programming Flow Adjust (Cal Dates and T emperatures Updated) V erify Document P ost-Adjustment R.
NI PXI-5422 Calibration Procedur e 10 ni.com Optional Calibration You can choose to skip the adjustme nt steps of the calibration procedure if the output error is within the calibr ation test limits or the pub lished specifications during the first verificat ion.
© National Instruments Corporation 11 NI PXI-5422 Calibration Procedure Figure 2. Option al Calibration Programming Flow Self-Calibrate V erify Document Pre-Adjustment Results Meets Calibration T est.
NI PXI-5422 Calibration Procedur e 12 ni.com External Calibration Requirements This section describes the test equipment and test conditions required for calibration. T est Equipment External calibration requ ires different equipmen t for each applicable specification.
© National Instruments Corporation 13 NI PXI-5422 Calibration Procedure External Calibration Procedures The complete external calibration pro cedure consists of self-calibrating, verifying the performance of the NI PXI-542 2, adjusting the calibration constants, and verifying again after the adjustments.
NI PXI-5422 Calibration Procedur e 14 ni.com V erifying NI PXI-5422 Specifications Note Always self-calibrate the NI PXI-5422 before beginning a verif ication procedure. This section provides instructions for verifyi ng the NI PXI-5422 specifications.
© National Instruments Corporation 15 NI PXI-5422 Calibration Procedure Figure 3. NI PXI-5422 Front Panel Connectors PFI 0 PFI 1 NI PXI- 5422 16-Bit 200 MS/s AWG ACCESS ACTIVE CLK IN CH 0 DIGIT AL DA.
NI PXI-5422 Calibration Procedur e 16 ni.com V erifying the Oscillato r Frequency Accuracy This test verifies the frequency accuracy of the oscillator on the NI PXI-5422. The verification involves generating a 10 MHz sine wave with the NI PXI-5422 and m easuring the sine wave frequency wi th one of the instruments from Tab le 2.
© National Instruments Corporation 17 NI PXI-5422 Calibration Procedure 5. Call niFgen_SetAttributeViReal64 to set the of fset (niFg en property node: Arbitrary Waveform O utput»Arbitrary Waveform O.
NI PXI-5422 Calibration Procedur e 18 ni.com A frequency error of 45 Hz for a 10 MHz signal corresponds to an error of 4.5 ppm. This limit accoun ts for the initial accuracy and the frequency de vi ation caused by temperature and aging. Refer to T abl e 3 for frequency ranges.
© National Instruments Corporation 19 NI PXI-5422 Calibration Procedure • IDQuery : VI_TRUE • resetDevice : VI_TRUE • vi : A pointer to a V iSession. The variable passed by reference through this parameter recei ves the value that identifies the session created by this function .
NI PXI-5422 Calibration Procedur e 20 ni.com 7. Call niFgen_SetAttributeViBoolean to enable the analog output (niFgen property node: Basic Operation»Output Enabled ) using the following parameters: .
© National Instruments Corporation 21 NI PXI-5422 Calibration Procedure 12. Call niFgen_SetAttributeViReal64 to set the of fset (niFg en property node: Arbitrary Waveform O utput»Arbitrary Waveform .
NI PXI-5422 Calibration Procedur e 22 ni.com Table 4. V alues for Verifying the Gain of the Main An alog Path Iteration Gain Ideal Pos it ive Full-Scale (V olts) Ideal Negative Full-Scale (V olts) Mea.
© National Instruments Corporation 23 NI PXI-5422 Calibration Procedure 21 0.018500 0.018500 – 0.018500 ±0.000530 ±0.000574 22 0.013000 0.013000 – 0.013000 ±0.000521 ±0.000552 23 0.009000 0.009000 – 0.009000 ±0.000514 ±0.000536 24 0.006500 0.
NI PXI-5422 Calibration Procedur e 24 ni.com 14. Call niFgen_SetAttributeViReal64 to set the gain (niFgen property node: Arbitrary Wavefo rm Output»Arbitrary Waveform Gain ) using the following param.
© National Instruments Corporation 25 NI PXI-5422 Calibration Procedure 23. Subtract the Ideal Negative Full-Scale value from the Measured Negative Full-Scale value and record the result under Error Negative Full-Scale . The Error Negative Full-Scal e v alue should be less than or equal to th e limit you ar e using.
NI PXI-5422 Calibration Procedur e 26 ni.com Table 5. V alues for Verifying the Offse t of the Main Analog Path Iteration Gain Ideal Pos it ive Offset (V olts) Ideal Negative Offset (V olts) Measured .
© National Instruments Corporation 27 NI PXI-5422 Calibration Procedure 21 0.018500 0.009250 – 0.009250 ±0.000532 ±0.0 00579 22 0.013000 0.006500 – 0.006500 ±0.000523 ±0.0 00555 23 0.009000 0.004500 – 0.004500 ±0.000516 ±0.0 00538 24 0.006500 0.
NI PXI-5422 Calibration Procedur e 28 ni.com 5. Call niFgen_SetAttributeViReal64 to set the of fset (niFgen property node: Arbitrary Waveform O utput»Arbitrary Waveform Offset ) using the following p.
© National Instruments Corporation 29 NI PXI-5422 Calibration Procedure 13. Measure the negati ve DC voltage out of the NI PXI-5422. Record negati ve DC vo ltage out measurement in the Measured Negative Offset column of T abl e 5.
NI PXI-5422 Calibration Procedur e 30 ni.com Table 6. Values for Verifying the Gain of the Direct An alog Path Iteration Gain Ideal Pos it ive Full-Scale (V olts) Ideal Negative Full-Scale (V olts) Me.
© National Instruments Corporation 31 NI PXI-5422 Calibration Procedure 4. Call niFgen_SetAttributeViReal64 to set the gain (niFgen property node: Arbitrary Wavef orm Output»Arbitrary Waveform Gain .
NI PXI-5422 Calibration Procedur e 32 ni.com 11. Measure the negati ve DC v oltage ou t of the NI PXI-5422. R ecord the negati ve DC voltage out measurement in the Measured Negative Full-Scale Value colu mn of T able 6.
© National Instruments Corporation 33 NI PXI-5422 Calibration Procedure 1. Call niFgen_InitExtCal (niFgen Init Ext Cal VI) to open an NI-FGEN external calibration session using the following parameters: • resourceName : The name of the device you want to calibrate.
NI PXI-5422 Calibration Procedur e 34 ni.com Figure 4. NI PXI-5422 External Calibration Procedure Initialize Ext Cal Session Initialize Analog Output Calibration Adjust Main P ath Pre-Amp Offset Adjus.
© National Instruments Corporation 35 NI PXI-5422 Calibration Procedure Initializing the External Calibration Session Call niFge n_InitExtCal (niFgen Ini t Ext Cal VI) to open an NI-F GEN external calibration session using the following parameters: • resourceName : The name of the device you want to calibrate.
NI PXI-5422 Calibration Procedur e 36 ni.com 3. Call niFgen_SetAttributeViInt32 to set the analog path v alu e (niFgen property node: Output Attributes»Ana log Path ) usin g the following parameters:.
© National Instruments Corporation 37 NI PXI-5422 Calibration Procedure 8. Call niFgen_SetAttributeViReal64 to set the post-amplifier attenuation (niFgen pro perty node: Calibra tion»Post -Amplifier.
NI PXI-5422 Calibration Procedur e 38 ni.com 2. Call niFgen_SetAttributeViReal64 to set the post-amplifier attenuation (niFgen pro perty node: Cali bration»Po st-Ampli fier Attenuation ) using th e f.
© National Instruments Corporation 39 NI PXI-5422 Calibration Procedure 5. Call niFgen_SetAttributeViBoolean to set the analog filter state (niFgen property node: Outpu t Attributes»Analog Fi lter E.
NI PXI-5422 Calibration Procedur e 40 ni.com f. Call niFgen_SetAttributeViInt32 to set the gain D A C v alue (niFgen property nod e: Calibration»Gain DAC Value ) using t he following parameters: • .
© National Instruments Corporation 41 NI PXI-5422 Calibration Procedure 8. Call niFgen_CalAdjustMainPathPreAmpOffset (niF gen Cal Adjust Main P ath Pre Amp Off set VI) using the follo wing parameters.
NI PXI-5422 Calibration Procedur e 42 ni.com 3. Call niFgen_SetAttributeViInt32 to set the of fset DA C value (niFgen property node: Calibra tion»Offset DAC Valu e ) using the following parameters: .
© National Instruments Corporation 43 NI PXI-5422 Calibration Procedure 6. Call niFgen_SetAttributeViReal64 to set the pre-amplifier attenuation (niFgen pro perty node: Calibratio n»Pre-Amplifi er A.
NI PXI-5422 Calibration Procedur e 44 ni.com g. Call niFgen_WriteBinary16AnalogStaticValue (niFgen Write Binary 16 Analog Static V alue VI) to set the main D A C value using the follo wing parameters: • vi : The session handle returned from niFgen_InitExtCal • channelName : "0" • value : – 29232 h.
© National Instruments Corporation 45 NI PXI-5422 Calibration Procedure Adjusting the Main Path Post-Amplifier Gain and Offset 1. Call niFg en_WriteBinary16AnalogStaticValue (niFgen Write Binary 16 A.
NI PXI-5422 Calibration Procedur e 46 ni.com 6. Call niFgen_SetAttributeViInt32 to set the analog path v alu e (niFgen property node: Output Attributes»Ana log Path ) usin g the following parameters:.
© National Instruments Corporation 47 NI PXI-5422 Calibration Procedure 8. T ake the follo wing voltage measur ements at the NI PXI-5422 CH 0 front panel connector i nto a high-impedance load: a.
NI PXI-5422 Calibration Procedur e 48 ni.com 9. Call niFgen_CalAdjustMainPathPostAmpGainAndO ffset (niFgen Cal Adjust Main Path Post Amp Gain And Offset VI) using the following parameters: • vi : Th.
© National Instruments Corporation 49 NI PXI-5422 Calibration Procedure 4. Call niFgen_SetAttributeViBoolean to set the analog filter state (niFgen property node: Outpu t Attributes»Analog Filter En.
NI PXI-5422 Calibration Procedur e 50 ni.com 9. Call niFgen_SetAttributeViInt32 to set the analog path v alu e (niFgen property node: Output Attributes»Ana log Path ) usin g the following parameters:.
© National Instruments Corporation 51 NI PXI-5422 Calibration Procedure g. Call niFgen_Commit (niFgen Commit VI) to comm it the attribute v alues to the device using the following parameter: • vi : The session handle ret urned from niFgen_InitExtCal h.
NI PXI-5422 Calibration Procedur e 52 ni.com 12. Call niFgen_CalAdjustDirectPathGain (niFgen Cal Adjust Direct Path Gain VI) using the following parameters: • vi : The session handle ret urned from .
© National Instruments Corporation 53 NI PXI-5422 Calibration Procedure 4. Call niFgen_SetAttributeViReal64 to set the of fset (niFg en property node: Arbitrary Waveform O utput»Arbitrary Waveform O.
NI PXI-5422 Calibration Procedur e 54 ni.com 9. Call niFgen_CreateArbWaveform (niFgen Create Arbitrary W av eform VI) using the following parameters: • vi : The session handle ret urned from niFgen_.
© National Instruments Corporation 55 NI PXI-5422 Calibration Procedure c. Call niFgen_InitiateGeneration (niFgen Initiate Generation VI) to initiat e the wav efor m generation using the following parameter: • vi : The session handle ret urned from niFgen_InitExtCal d.
NI PXI-5422 Calibration Procedur e 56 ni.com 5. Call niFgen_SetAttributeViInt32 to set the of fset DA C value (niFgen property node: Calibra tion»Offset DAC Valu e ) using the following parameters: .
© National Instruments Corporation 57 NI PXI-5422 Calibration Procedure • vi : The session handle ret urned from niFgen_InitExtCal • channelName : "0" • attributeID : NIFGEN_ATTR_OU TPUT_ENABLED • value : VI_TRUE 11.
NI PXI-5422 Calibration Procedur e 58 ni.com • returnCalibratedValue : VI_FALSE • calADCValue : A V iReal64 variable. The v ariabl e passed by reference through this parameter receiv es the voltage measured by th e onboard ADC. Th is v alue is cal ADC measurement 0 , which is used in step 32.
© National Instruments Corporation 59 NI PXI-5422 Calibration Procedure 27. Call niFgen_ReadCalADC (niFgen Read CAL ADC VI) to measure the analog output voltage with the onboard calibratio n ADC usin.
NI PXI-5422 Calibration Procedur e 60 ni.com 33. Call niFgen_SetAttributeViBoolean to disable the analog output (niFgen property node: Basic Operation»Outpu t Enabled ) using the following parameters.
© National Instruments Corporation 61 NI PXI-5422 Calibration Procedure Calibration Utilities NI-FGEN supports several calibr ation utilities th at allow you to retrieve information about adjustments.
NI PXI-5422 Calibration Procedur e 62 ni.com NI-FGEN NI-FGEN provides a full com plement of calibration util ity functions and VIs. Refer to the NI Signal Generators Help for t he complete functio n reference.
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