Maintaining the NPD 14
Maintaining Your GC 285
To Check the 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
< 2.0 pA.
The output should slowly drop towards 0.0 pA, and
should stabilize in the tenths of a picoamp. Current
> 2.0pA indicates a problem.