Other Problems And Possible Causes - Knauer Smartline 2300 Benutzerhandbuch

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Other problems and possible causes

Table 5
Problem Probable Cause
light intensity A bubble in sample or
is too low reference cell.
(80 % or
less)
Dirty cell
Leaking cell
Sensitivity is Dirty cell
too low
Calibration not ok
Baseline Bubbles
spikes
High drift Instrument needs to
warm up
Temperature fluctuations Work at constant temperature.
Leaking cell
Leaking valve
High noise Light intensity is too low
Electrostatic or electrical
interference
A bubble in the sample or
reference cell.
Periodic interferences
(only when the pump is
running)
Periodical interferences
caused by dripping of the
eluent from the outlet
capillary's end.
Dirty cell
Other Problems
Solution
Flush sample and reference
cell several times. Please use
for example methanol or
water methanol mixtures
instead of pure water. Check
I and I .
1 2
Clean the cell.
Remove the leak.
Clean the cell.
Calibrate the detector.
Look for a leak on the pump's
inlet.
Use a degasser.
Flush the cell at a high flow
rate
Wait until the instrument has
warmed up.
Remove the leak.
Remove the leak.
See above.
Try to prevent electrostatical
interference and check
grounding of the instruments.
It might help to connect the
instrument to a different
electrical circuit.
See above.
Try to reduce the pulsation,
for example with a pulse
dampener.
Put the outlet capillary's end
into the solvent.
Clean the cell.