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NI 5922 Calibration Procedure

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© National Instruments

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9

External Calibration Requirements

Test Equipment

Table 2 lists the equipment required for externally calibrating the NI 5922. If you do not have 
the recommended instruments, use these specifications to select a substitute calibration standard.

Note

The delay times indicated in this procedure apply specifically to the 

Fluke 9500B calibrator. If you use a different calibrator, you may need to increase 
these delay times. This increase varies between calibrator models.

Test Conditions

Follow these guidelines to optimize the connections and the environment during calibration:

Always connect the scope calibrator to the input BNC of the oscilloscope, or use a short 
50

 BNC coaxial cable if necessary. Long cables and wires act as antennas, picking up 

extra noise that can affect measurements.

Keep relative humidity between 10 and 90%, non-condensing.

Maintain an ambient temperature of 23 ±5 °C.

Allow a warm-up time of at least 15 minutes after NI-SCOPE loads. Unless manually 
disabled, NI-SCOPE automatically loads with the operating system and enables the device. 
The warm-up time ensures that the measurement circuitry of the NI 5922 is at a stable 
operating temperature.

Ensure that the PXI chassis fan speed is set to HI, that the fan filters are clean, and that the 
empty slots contain filler panels.

Plug the PXI chassis or PC and the calibrator into the same power strip to avoid ground 
loops.

Table 2.  

Required Equipment for NI 5922 External Calibration

Required 

Equipment 

Recommended 

Equipment 

Parameter 

Measured

Specification

Signal Generator

Fluke 9500B 
oscilloscope 
calibrator

9510 Test Head

(or Wavetek 9500 
with 
high-stability 
reference option)

Timing

2 ppm frequency 
accuracy

DC Source

Fluke 5700

Vertical Gain

DC ±50 ppm into 1 M

BNC cable

50

Summary of Contents for NI PCI-5922

Page 1: ...alibration 2 External Calibration 2 Calibration Intervals 2 Software and Documentation 2 Documentation 4 Self Calibration Procedures 4 MAX 5 Scope SFP 5 NI SCOPE 5 External Calibration Options 6 Complete Calibration 7 Optional Calibration 7 External Calibration Requirements 9 Test Equipment 9 Test Conditions 9 External Calibration Procedures 10 Verifying NI 5922 Specifications 10 Vertical Offset A...

Page 2: ...ensate for environmental changes Caution Although you can use self calibration repeatedly self calibrating the NI 5922 more than a few times a day may cause excessive wear on the relays over time The measurement accuracy requirements of your application determine how often you should externally calibrate the NI 5922 NI recommends that you perform a complete external calibration at least once every...

Page 3: ...scription IVI Bin niscope_32 dll NI SCOPE driver containing the entire NI SCOPE API including calibration functions IVI Lib msc niscope lib NI SCOPE library for Microsoft C containing the entire NI SCOPE API including calibration functions LabVIEW version examples instr niScope Directory of LabVIEW NI SCOPE example VIs including self calibration access the calibration example from the LabVIEW func...

Page 4: ...e Self calibrate the oscilloscope before you perform verification NI SCOPE includes self calibration example programs for LabVIEW CVI and Microsoft Visual C You can initiate self calibration using Measurement Automation Explorer MAX using the Scope Soft Front Panel SFP or programmatically using NI SCOPE NI PXI PCI 5922 Getting Started Guide Contains NI SCOPE installation hardware installation and ...

Page 5: ...to the oscilloscope 2 Launch the Scope SFP by selecting Start Programs National Instruments NI SCOPE Scope Soft Front Panel 3 Select the device you want to calibrate using the Select Device dialog box or by selecting Edit Change Device 4 Launch the Calibration dialog box by selecting Utility Self Calibration 5 Click OK to begin self calibration NI SCOPE To self calibrate the NI 5922 programmatical...

Page 6: ...r to limits given in Tables 3 through 7 This document provides two sets of test limits for most verification stages the calibration test limits and the published specifications The calibration test limits are more restrictive than the published specifications If all of the measurement errors determined during verification fall within the calibration test limits the device is guaranteed to meet or ...

Page 7: ...fication fall within the calibration test limits the device is guaranteed to meet or exceed its published specifications for a full calibration interval In this case you can update the calibration date effectively resetting the calibration interval without actually performing an adjustment Refer to the Adjusting the NI 5922 section for more information If all of the measurement errors determined d...

Page 8: ...igure 2 Optional Calibration Programming Flow Self Calibrate Verify Yes No Meets Published Specifications Yes Results Within Published Specs Adjustment Optional No Adjust Cal Dates and Temperatures Updated No Calibration Verification Complete Yes Document Post Adjustment Results Document Pre Adjustment Results Review Verification Adjustment Procedure or Return Device No Yes Meets Calibration Test ...

Page 9: ...p extra noise that can affect measurements Keep relative humidity between 10 and 90 non condensing Maintain an ambient temperature of 23 5 C Allow a warm up time of at least 15 minutes after NI SCOPE loads Unless manually disabled NI SCOPE automatically loads with the operating system and enables the device The warm up time ensures that the measurement circuitry of the NI 5922 is at a stable opera...

Page 10: ...is section begin with niScope_init niScope Initialize VI with resetDevice set to NISCOPE_VAL_TRUE and end with niScope_close niScope Close VI If any of these tests fail immediately after you perform an external adjustment verify that you have met the required test conditions listed in the External Calibration Requirements section before you return the oscilloscope to NI for repair Vertical Offset ...

Page 11: ...t corresponds to the vertical range used If the result is within the selected test limit the device has passed this portion of the verification 7 Repeat steps 1 through 6 for each iteration in Table 3 8 Repeat steps 1 through 7 for channel 1 changing the value of the channelList parameter from 0 to 1 Noise Complete the following steps to verify noise performance of the NI 5922 You must verify both...

Page 12: ...er vi The instrument handle you obtained from niScope_init 6 Call niScope_FetchArrayMeasurement niScope Fetch Array Measurement VI with the following parameters channelList 0 timeout 5 0 arrayMeasFunction NISCOPE_VAL_FFT_AMP_SPECTRUM_VOLTS_RMS measWfmSize 1 7 Calculate the noise value from the returned voltage array V n using the following formula where i is obtained from Table 4 a Add up the squa...

Page 13: ...mpedance NISCOPE_VAL_50_OHM maxInputFrequency 0 3 Call niScope_ConfigureVertical niScope Configure Vertical VI with the following parameters channelList 0 range 2 offset 0 0 coupling NISCOPE_VAL_DC probeAttenuation 1 0 enabled NISCOPE_VAL_TRUE Table 4 NI 5922 Noise Performance Iteration Range V Sample Rate S s i Calibration Test Limits Published Specifications 1 2 50 k 132 0 95 μV 1 μV 2 2 100 k 6...

Page 14: ...h the following parameters channelList 0 inputImpedance NISCOPE_VAL_1_MEG_OHM maxInputFrequency 0 8 Call niScope_InitiateAcquisition niScope Initiate Acquisition VI with the following parameter vi The instrument handle you obtained from niScope_init 9 Call niScope_FetchMeasurement niScope Fetch Measurement VI with the following parameters channelList 0 timeout 1 0 scalarMeasFunction NISCOPE_VAL_DC...

Page 15: ...et 0 0 coupling NISCOPE_VAL_DC probeAttenuation 1 0 enabled NISCOPE_VAL_TRUE 3 Call niScope_ConfigureHorizontalTiming niScope Configure Horizontal Timing VI with the following parameters minSampleRate 10 000 000 minNumPts 100 000 refPosition 50 0 numRecords 1 enforceRealtime NISCOPE_VAL_TRUE 4 Call niScope_Commit niScope Commit VI with the following parameter vi The instrument handle you obtained ...

Page 16: ...s a percentage of input using the following formula where a the measured positive voltage b the measured negative voltage c the applied positive voltage d the applied negative voltage Compare the resulting percent error to the Calibration Test Limits or the Published Specifications listed in Table 6 If the result is within the selected test limit the device has passed this portion of the verificat...

Page 17: ...ing niScope Configure Horizontal Timing VI with the following parameters minSampleRate 15 000 000 minNumPts 1 000 000 refPosition 50 0 numRecords 1 enforceRealtime NISCOPE_VAL_TRUE 4 Call niScope_Commit niScope Commit VI with the following parameter vi The instrument handle you obtained from niScope_init 5 Connect the scope calibrator to the channel 0 input of the oscilloscope Configure the calibr...

Page 18: ...ion date and temperature in the EEPROM of the oscilloscope Note If the oscilloscope passed the entire verification procedure within the calibration test limits and you do not want to perform an adjustment you can update the calibration date and onboard calibration temperature without making any adjustments by completing only steps 4 and 13 in this section Complete all of the following steps to ext...

Page 19: ...tle 10 Call niScope_CalAdjustRange niScope Cal Adjust Range VI with the following parameters channelName 1 range 0 stimulus 4 0 11 Disconnect or disable all inputs to the oscilloscope 12 Call niScope_CalSelfCalibrate niScope Cal Self Calibrate VI with the following parameters channelList VI_NULL option VI_NULL 13 Call niScope_CalEnd with the following parameters sessionHandle The instrument handle...

Page 20: ...information from My System Devices and Interfaces 2 Select the Calibration tab You should see information about the last date and temperature for both external and self calibration NI SCOPE NI SCOPE provides a full complement of calibration utility functions and VIs Refer to the NI High Speed Digitizers Help for the complete function reference and VI reference for the following utility functions n...

Page 21: ...e is your complete resource for technical support At ni com support you have access to everything from troubleshooting and application development self help resources to email and phone assistance from NI Application Engineers Visit ni com services for NI Factory Installation Services repairs extended warranty and other services Visit ni com register to register your National Instruments product P...

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