Agilent InfinityLab LC Series RID User Manual
122
8
Test Functions
ASTM Drift and Noise Test
Evaluation
For the Instant Pilot
Rescale
the plot and measure the baseline noise and drift on
the screen. If a printer is configured for the instrument the plot can be printed by
pressing the
m
key and selecting
Print Plot
.
The following values are calculated automatically by the Agilent ChemStation.
•
Noise (ASTM):
The short term noise in nRIU based on ASTM method
E-1303-95
Practice for Refractive Index Detectors used in Liquid
Chromatography
using 0.5 minute segments.
•
Wander:
The long term noise in nRIU based on ASTM method E-1303-95
Practice for Refractive Index Detectors used in Liquid Chromatography
using
0.5 minute segments.
•
Drift:
The drift in nRIU/hour based on ASTM method E-1303-95
Practice for
Refractive Index Detectors used in Liquid Chromatography
measured over 20
minutes.
Factors that will affect the baseline stability include:
•
Variations in the optics or eluent temperature
•
Pressure fluctuations in the sample cell
•
The quality of the water used
•
Air bubbles in the flow cell
For diagnosing signal problems refer to chapter
"Troubleshooting and
Diagnostics"
.