Metrohm 944 Professional UV/VIS Detector Vario - Manual (Page 42)

7.1 Problems and their solutions
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944 Professional UV/VIS Detector Vario (2.944.0010)
7 Troubleshooting
7.1 Problems and their solutions
Problem Cause Remedy
No measuring sig-
nal. The lamp is not lit. Replace the UV lamp (see Chapter 6.4, page
25) or the VIS lamp (see Chapter 6.5, page
28).
The baseline has a
large amount of
noise. Air bubbles are trapped in
the flow-through cell. ￭ Clean the flow-through cell (see Chapter
6.7, page 29).
￭ Ensure that the PEEK capillary (6.1831.100)
is connected to the cell outlet.
￭ Use the eluent degasser.
Flow-through cell – The
lenses are dirty. Clean the flow-through cell (see Chapter 6.7,
page 29).
UV lamp – The radiation is
too weak. Check the intensity spectrum (see Chapter 4,
page 21). If the intensity is too low, replace
the UV lamp (see Chapter 6.4, page 25).
The eluent's absorption is
too strong. Change the eluent.
The wavelength is unsuit-
able. Set a different wavelength in MagIC Net.
The baseline is drift-
ing. The flow-through cell is
leaky. Check all connections and fix the leak.
Thermal equilibrium is not
attained. Ensure a constant temperature.
Lamp does not
ignite. The lamp is defective. Replace the UV lamp (see Chapter 6.4, page
25) or the VIS lamp (see Chapter 6.5, page
28).