Keithley 6485 Instruction Manual page 210

16-10 Calibration
11.
12.
13.
Table 16-5
2nA to 2 µ A range calibration summary
Model 6485 Range
2nA
20nA
200nA
2µA
1
Nominal resistance values.
2
Nominal currents. Calculate actual currents from calibrator voltage and actual standard resistor value: I = V/R. Calibrate zero,
positive full-scale, and negative full-scale for each range.
Set the calibrator output voltage to –2.000000V, then calculate the calibration cur-
rent from the calibrator voltage and standard resistor value: I = V/R. Adjust the
Model 6485 display to agree with the calculated current, then press ENTER to
complete calibration of the present range.
Press EXIT to return to normal display.
Repeat steps 3 through 12 for the 20nA through 2µA ranges using
guide. Be sure to make connections to the correct standard resistor and set the cali-
brator voltages to the correct values.
Calibrator Voltages
0V
+2.000000V
-2.000000V
0V
+2.000000V
-2.000000V
0V
+20.00000V
-20.00000V
0V
+200.0000V
-200.0000V
Standard Resistors
1GΩ
1GΩ
1GΩ
100MΩ
100MΩ
100MΩ
100MΩ
100MΩ
100MΩ
100MΩ
100MΩ
100MΩ
Model 6485 Instruction Manual
Table 16-5
1
Calibration Currents
0nA
+2nA
-2nA
0nA
+20nA
-20nA
0nA
+200nA
-200nA
0µA
+2µA
-2µA
as a
2