Bio-Rad ChromLab™ Software - Manual (Page 256)

B | Troubleshooting the Instrument
254 | NGC Chromatography Systems and ChromLab Software
The UV baseline is
unstable or noisy
(continued).
The UV baseline shows
a reproducible zig-zag
or sawtooth trace
(continued).
UV or UV/Vis lamps are dirty or are
close to the end of their usable
life. Check the lamp usage values in
the System Information dialog
box:
1. From the System Control tab
in ChromLab open File > System
Information > Detector tab.
2. Click Get Lamp Status.
 Use the lamp usage values
(close to 2,000 hours for the
deuterium and tungsten
lamps; close to 5,000 hours or
100% PWM for LEDs), to
determine if the lamps are
nearing their end of life.
To change the UV flow cell see
Replacing the UV Flow Cell on
page
196 .
To change the lamps:
 See Replacing the Single-
Wavelength UV Detector LED
on page
201
 See Replacing the Multi-
Wavelength UV/Vis Detector
Lamps on page
209
Note: For more information
about the Detector tab, see
the chapter System Control
in the NGC
Chromatography Systems
and ChromLab Software
User Guide.
Excessive pump
pulsations exhibit as
regular noise on the
baseline. Air bubbles trapped in the pump
heads can produce exaggerated
pulsations, which appear as noisy
UV baselines. Purge the pump heads to
remove bubbles.
Symptom Possible Cause Possible Solution