Measurement Computing Data Translation DT9857, Руководство пользователя

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Calibration
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Calibrating the Analog Output Subsystem
To calibrate the analog output circuitry, you need to connect an external precision voltmeter to
the analog output channels of the DT9857 or DT9857E module.
Do the following to calibrate the analog output circuitry:
1. Select the D/A Calibration tab of the calibration utility.
2. Under the Calibration Settings area of the window, select the output frequency, in Hertz.
3. Under the Channel Selection area of the window, select the analog output channel to
calibrate.
4. Connect an external precision voltmeter to the selected analog output channel.
5. In the DAC Output Voltage box, select 0 V .
6. Under the Calibration Controls area of the window, adjust the offset by entering values
between 0 and 255 in the DAC Offset edit box or by clicking the up/down buttons until
the voltmeter reads 0 V.
7. In the DAC Output Voltage box, select 9.375 V .
8. Under the Calibration Controls area of the window, adjust the gain by entering values
between 0 and 255 in the DAC Gain edit box or by clicking the up/down buttons until
the voltmeter reads 9.375 V.
9. Repeat steps 2 to 7 for each analog output channel on the module.
Note: At any time, you can click Restore Factory Settings to reset the D/A calibration
values to their original factory settings. This process will undo any D/A calibration settings.
Once you have finished this procedure, the analog output circuitry is calibrated. To close the
calibration utility, click the close box in the upper right corner of the window.