Keithley KUSB-3100, User Manual

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Chapter 6
82
Calibrating the Analog Input Subsystem
This section describes how to use the KUSB-3100 Calibration Utility
to calibrate the analog input subsystem of a KUSB-3100 module.
Connecting a Precision Voltage Source
To calibrate the analog input circuitry, you need to connect an
external precision voltage source to Analog In 0 (AD Ch0) of the
KUSB-3100 module.
Using the Auto-Calibration Procedure
Auto-calibration is the easiest to use and is the recommended
calibration method. To auto-calibrate the analog input subsystem,
perform the following steps:
1. Select the A/D Configuration tab of the KUSB-3100 Calibration
Utility.
2. Set the voltage supply on AD Ch0 to 0 V.
3. Click Start Auto Calibration .
A message appears notifying you to verify that 0 V is applied to AD
Ch0.
4. Check that the supplied voltage to AD Ch0 is 0V, then click OK .
The offset value is calibrated. When the offset calibration is complete, a
message appears notifying you to set the input voltage of AD Ch 0 to
+9.375 V.
5. Check that the supplied voltage to AD Ch0 is +9.375V, then click
OK .
The gain value is calibrated.
6. Click OK to finalize the analog input calibration process.