Remote Preamp Current Measurement Accuracy - Keithley 6430 Instruction Manual

18-24 Performance Verification

Remote PreAmp current measurement accuracy

Follow the steps below to verify that Model 6430 Remote PreAmp current measurement
accuracy is within specified limits. The procedure involves applying accurate currents from the
Model 6430 current source and then verifying that Model 6430 current measurements are
within required limits.
1 µ A-100mA range accuracy
1.
2.
3.
4.
NOTE
5.
Table 18-12
Remote PreAmp 1µA-100mA range measurement accuracy limits
Model 6430 range
1
Measure range coupled to source range when simultaneously sourcing and measuring current.
2
As measured by precision digital multimeter. Use closest possible value, and modify reading limits accord-
ingly if necessary.
With the power off, connect the digital multimeter to the PreAmp IN/OUT HIGH jack
as shown in Figure 18-6. (Connect the IN/OUT HIGH jack to the DMM AMPS and
INPUT LO jacks using the adapters shown. Use a triax-to-BNC adapter that connects
triax shell to BNC shell, and be sure to connect the cable shield to DMM INPUT LO.)
Select the multimeter DC current function.
Set the Model 6430 to both source and measure current by pressing the SOURCE I and
MEAS I keys, and make sure the source output is turned on.
Verify measure current accuracy for the currents listed in Table 18-12. For each
measurement:
• Select the correct source range.
• Set the Model 6430 source output to the correct value as measured by the digital
multimeter.
• Verify that the Model 6430 current reading is within the limits given in the table.
It may not be possible to set the current source to the specified value. Use the closest
possible setting, and modify reading limits accordingly.
Repeat the procedure for negative calibrator currents with the same magnitudes as those
listed in Table 18-12.
1
1µA
10µA
100µA
1mA
10mA
100mA
2
Source current
1.000000µA
10.00000µA
100.000µA
1.00000mA
10.0000mA
100.000mA
Model 6430 current reading
limits (1 year, 18°-28°C)
0.99920 to 1.00080µA
9.9930 to 10.0070µA
99.969 to 100.031µA
0.99967 to 1.00033mA
9.9959 to 10.0041mA
99.939 to 100.061mA