98 Troubleshooting
8 Troubleshooting Tasks
To Measure NPD Leakage Current
1 Load the analytical method.
2 Set the NPD Adjust Offset to Off and the Bead Voltage to 0.00 V.
• Leave the NPD at operating temperature.
• Leave flows on or off.
3 Press [Front Detector] or [Back Detector], then scroll to Output.
4 Verify that the output (leakage current) is stable and
< 1.0 pA.
5 The output should slowly drop toward 0.0 pA, and should
stabilize in the tenths of a picoamp. Current > 2.0pA
indicates a problem.