Decrease In Sensitivity; A Noisy Signal Is Observed - Agilent Technologies 1260 Infinity User Manual

6 Troubleshooting and Diagnostics
Troubleshooting Based on Instrument Signals

Decrease in Sensitivity

If noise tests did not show that the problem could be caused by the application
or system, a decrease in the sensitivity is often caused by the nebulizer (main
cause) or the detector sensing section.
If noise tests pass but the signal heights/areas for known standards are too
low, the nebulizer might need to be replaced. Please note that the root cause
might also be in a different module, e.g. volumes injected by the autosampler
might be too low or dead volumes in capillary connections cause peak
broadening.
If the stray light test gives signals which are too low
✔
✔

A Noisy Signal is Observed

High noise is often due to a lack of maintenance. The detector should be cleaned on a
N O T E
routine basis.
If the signal is noisy, apply noise tests in order to ensure that the high noise is
not due to the mobile phase or the column. Then:
1 Do a general inspection as described in
2 Clean the nebulizer as described in
3 Exchange the nebulizer.
80
Use the instrument keyboard for checking if the life time of the light source
has been exceeded. If needed, please contact your Agilent service
representative for a replacement.
Set the stray light to the original value. See
Screen" on page 102.
"The Light source Normalization
"General Inspection"
"Cleaning the Nebulizer"
Agilent 1260 Infinity ELSD User Manual
on page 82
on page 86.