Dataq DI-720-EN, User Manual

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DI–720/DI–722/DI–730 Series User Manual
Calibration Verification
33
Offset Calibration Verification (DI-720 and DI-722 Instruments Only)
1. Connect your voltage calibrator, or combination DVM and voltage source to your DI-7XX instrument as shown
above. Apply zero volts to the instrument (or short the instrument's analog channel input to ground).
2. Open the W
IN
D
AQ
/Lite/Pro/Pro+ data acquisition screen. Enable the channel you will use to quantify offset.
Since all channels are adjusted together, any channel may be selected. Enable a maximum burst sample rate of
50,000 Hz by selecting EDIT-PREFERENCES-MAX SAMPLE RATE. Enable a W
IN
D
AQ
sample rate of 50 Hz.
Set the Acquisition Mode to AVERAGE and the gain factor to 1 through W
IN
D
AQ
’s CHANNEL SETTINGS
menu for the selected channel.
3. Referring to W
IN
D
AQ
software's voltage display for the channel you're evaluating, compare this value to that
given in the OFFSET column of TABLE (1) for the selected gain factor.
4. Repeat steps 2 and 3 using a gain of 2, 4 and 8 for the selected channel.
5. If any readings are out of the acceptable ranges described in TABLE (1) arrange to have your instrument recali-
brated by DATAQ Instruments.
Full Scale (Span) Calibration Verification (DI-720 and DI-722 Instruments
Only)
1. Referring again to TABLE (1) set the instrument's gain to 1 and apply the voltage indicated by the SPAN VOLT-
AGE column of TABLE (1) to the selected channel. Note that since all channels are calibrated together, any
channel may be selected.
**NOTE: For DI-722 general purpose channels, refer to TABLE 1. For DI-722 differ-
ential channels, refer to TABLE 2 .
2. Verify the reading by comparing the value displayed by W
IN
D
AQ
software with the value of TABLE (1) in the
SPAN ACCURACY column.
3. Repeat for gain selections of 2, 4, and 8.
4. If any readings are out of the acceptable ranges described in TABLE (1) arrange to have your instrument recali-
brated by DATAQ Instruments.
TABLE 1
Gain Factor Offset @ 0V Span Voltage Span Accuracy*
1 0V ±20mV 9.800V 9.800V ±25mV
2 0V ±10mV 4.900V 4.900V ±12.5mV
4 0V ±5mV 2.400V 2.400V ±6.25mV
8 0V ±5mV 1.200V 1.200 ±3.125mV
* Excludes offset errors.
TABLE 2 (Only applicable for DI-722 differential channels)
Gain Factor Offset @ 0V Span Voltage Span Accuracy*
1 0V ±40mV 19.600V 19.600V ±50mV
2 0V ±20mV 9.800V 9.800V ±25mV
4 0V ±10mV 4.800V 4.800V ±12.5mV
8 0V ±10mV 2.400V 2.400 ±6.25mV
* Excludes offset errors