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AO Waveform Calibration Procedure for NI-DAQmx

8

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2. Choose the table from th

AO Device Test Limits

 

section that 

corresponds to the device you are verifying. This table shows all 
acceptable settings for the device. Although NI recommends that you 
verify all ranges, you may want to save time by checking only the 
ranges used in your application.

3.

Create a task using 

DAQmxCreateTask

4.

Add an AO voltage task using 

DAQmxCreateAOVoltageChan

 

(

DAQmx Create Virtual Channel VI

) and configure the channel, 

AO 0. Use the tables in the 

AO Device Test Limits

 section to determine 

the minimum and maximum values for your device.

AO 27

AO 27 (pin 14)

AO GND (pin 48)

AO 28

AO 28 (pin 13)

AO GND (pin 47)

AO 29

AO 29 (pin 46)

AO GND (pin 12)

AO 30

AO 30 (pin 11)

AO GND (pin 45)

AO 31

AO 31 (pin 10)

AO GND (pin 44)

NI-DAQ Function Call

LabVIEW Block Diagram

Call 

DAQmxCreateTask

 with 

the following parameters:

taskName

MyAOVoltageTask

taskHandle

&taskHandle

LabVIEW does not require this step.

NI-DAQ Function Call

LabVIEW Block Diagram

Call 

DAQmxCreateAOVoltageChan

 

with the following parameters:

taskHandle

taskHandle

physicalChannel

dev1/aoO

nameToAssignToChannel

AOVoltageChannel

minVal

-10.0

maxVal

10.0

units

DAQmx_Val_Volts

customScaleName

NULL

Table 2.  

Connecting the DMM to AO <8..31> on the NI 6723 (Continued)

Output Channel

DMM Positive Input

DMM Negative Input

Summary of Contents for NI-DAQ mx

Page 1: ...5 Calibration Process Overview 5 Initial Setup 6 AO Verification Procedure 6 Analog Output Verification 6 Counter Verification 10 AO Adjustment Procedure 12 AO Device Test Limits 14 Using the Tables 14 Range 14 Test Point 14 24 Hour Ranges 14 1 Year Ranges 14 Counters 14 NI 6711 6713 12 Bit Resolution 15 NI 6722 6723 13 Bit Resolution 15 NI 6731 6733 16 Bit Resolution 16 ...

Page 2: ...Monospace text denotes text or characters that you should enter from the keyboard sections of code programming examples and syntax examples This font is also used for the proper names of disk drives paths directories programs subprograms subroutines device names functions operations variables filenames and extensions monospace italic Italic text in this font denotes text that is a placeholder for ...

Page 3: ...ual Basic and Borland C Documentation If you are using the NI DAQmx driver the following documents are your primary references for writing your calibration utility The NI DAQmx C Reference Help includes information about the functions in the driver The DAQ Quick Start Guide for NI DAQ 7 3 or later provides instructions for installing and configuring NI DAQ devices The NI DAQmx Help includes inform...

Page 4: ...e use a high precision voltage source that is at least 50 ppm accurate for 12 and 13 bit boards and 10 ppm for 16 bit boards DMM NI 4070 If that instrument is unavailable use a multi ranging 5 5 digit DMM with an accuracy of 40 ppm 0 004 Counter Hewlett Packard 53131A If that instrument is unavailable use a counter accurate to 0 01 Low thermal copper EMF plug in cables Fluke 5440A 7002 Do not use ...

Page 5: ...ise and thermal offsets Maintain a temperature between 18 and 28 C To operate the module at a specific temperature outside this range calibrate the device at that temperature Keep relative humidity below 80 Allow a warm up time of at least 15 minutes to ensure that the measurement circuitry is at a stable operating temperature Calibration Process This section provides instructions for verifying an...

Page 6: ...igured with MAX it is assigned a device identifier Each function call uses this identifier to determine which DAQ device to calibrate AO Verification Procedure Verification determines how well the DAQ device is meeting its specifications By performing this procedure you can see how your device has operated over time You can use this information to help determine the appropriate calibration interva...

Page 7: ...pin 66 AO 11 AO 11 pin 65 AO GND pin 31 AO 12 AO 12 pin 30 AO GND pin 64 AO 13 AO 13 pin 29 AO GND pin 63 AO 14 AO 14 pin 62 AO GND pin 28 AO 15 AO 15 pin 27 AO GND pin 61 AO 16 AO 16 pin 26 AO GND pin 60 AO 17 AO 17 pin 59 AO GND pin 25 AO 18 AO 18 pin 24 AO GND pin 58 AO 19 AO 19 pin 23 AO GND pin 57 AO 20 AO 20 pin 55 AO GND pin 21 AO 21 AO 21 pin 20 AO GND pin 54 AO 22 AO 22 pin 19 AO GND pin ...

Page 8: ...rmine the minimum and maximum values for your device AO 27 AO 27 pin 14 AO GND pin 48 AO 28 AO 28 pin 13 AO GND pin 47 AO 29 AO 29 pin 46 AO GND pin 12 AO 30 AO 30 pin 11 AO GND pin 45 AO 31 AO 31 pin 10 AO GND pin 44 NI DAQ Function Call LabVIEW Block Diagram Call DAQmxCreateTask with the following parameters taskName MyAOVoltageTask taskHandle taskHandle LabVIEW does not require this step NI DAQ...

Page 9: ... these limits the test is considered to have passed 8 Clear the acquisition using DAQmxClearTask DAQmx Clear Task VI NI DAQ Function Call LabVIEW Block Diagram CallDAQmxStartTask with the following parameters taskHandle taskHandle NI DAQ Function Call LabVIEW Block Diagram Call DAQmxWriteAnalogF64 with the following parameters taskHandle taskHandle numSampsPerChan 1 autoStart 1 timeout 10 0 dataLa...

Page 10: ...nly verification can be performed Perform checks using the following procedure 1 Connect your counter positive input to CTR 0 OUT pin 2 and your counter negative input to D GND pin 35 2 Create a task using DAQmxCreateTask 3 Add a counter output channel to the task using DAQmxCreateCOPulseChanFreq DAQmx Create Virtual Channel VI and configure the channel NI DAQ Function Call LabVIEW Block Diagram C...

Page 11: ...n the device table If the value falls between these limits the test is considered to have passed 7 Clear the generation using DAQmxClearTask DAQmx Clear Task VI 8 Disconnect the counter from your device You have verified the counter on your device NI DAQ Function Call LabVIEW Block Diagram Call DAQmxCfgImplicitTiming with the following parameters taskHandle taskHandle sampleMode DAQmx_Val_ContSamp...

Page 12: ...tory The default password is NI To perform adjustment of the device with a calibrator complete the following steps 1 Connect the calibrator to the device according to Table 3 2 Set your calibrator to output a voltage of 5 V 3 Open a calibration session on your device using DAQmxInitExtCal DAQmx Initialize External Calibration VI The default password is NI Table 3 Connecting the Calibrator to the D...

Page 13: ...sconnect the calibrator from the device The device is now calibrated with respect to your external source After adjusting the device you may want to verify the analog output operation To do this repeat the steps in the AO Verification Procedure section using the 24 hour test limits in the AO Device Test Limits section NI DAQ Function Call LabVIEW Block Diagram Call DAQmxAOSeriesCalAdjust with the ...

Page 14: ...ocation and Value Location refers to where the test value fits within the test range Pos FS stands for positive full scale and Neg FS stands for negative full scale Value refers to the voltage value to be verified and is in volts 24 Hour Ranges The 24 Hour Ranges column contains the Upper Limits and Lower Limits for the test point value That is when the device is within its 24 hour calibration int...

Page 15: ...92 9 9981208 10 10 Neg FS 9 9900000 9 9977012 9 9822988 9 9981208 9 9818792 Table 5 NI 6711 6713 Counter Values Set Point MHz Upper Limit MHz Lower Limit MHz 5 5 0005 4 9995 Table 6 NI 6722 6723 Analog Output Values Range V Test Point 24 Hour Ranges 1 Year Ranges Minimum Maximum Location Value V Lower Limit V Upper Limit V Lower Limit V Upper Limit V 10 10 0 0 0 0 0070095 0 0070095 0 0070095 0 007...

Page 16: ...ents 2004 National Instruments Corp All rights reserved 370938A 01 Jul04 370938A 01 NI 6731 6733 16 Bit Resolution Table 8 NI 6731 6733 Analog Output Values Range V Test Point 24 Hour Ranges 1 Year Ranges Minimum Maximum Location Value V Lower Limit V Upper Limit V Lower Limit V Upper Limit V 10 10 0 0 0 0 0010270 0 0010270 0 0010270 0 0010270 10 10 Pos FS 9 9900000 9 9885335 9 9914665 9 9883636 9...

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