Horiba Scientific FluoroMax-4 Operation Manual page 120

® ®
FluoroMax -4 & FluoroMax -4P with USB rev. D (30 Jul 2012)
No change in signal
intensity.
No signal.
Erratic signal.
Raman band super-
imposed on fluores-
cence scan.
Large off-scale peak
at twice the excita-
tion wavelength.
Stray light in emis-
sion scan (also see
example in this chap-
ter).
Corrected excitation
spectrum curves up-
ward ~240–270 nm.
Noisy spectrum with
magnetic stirrer.
Communication
problems between
computer and in-
strument.
and self-absorption.
Detectors are saturated.
Lamp is not on.
Detectors are saturated.
Lamp unstable.
Light leaks.
Sample has particles that
scatter light irregularly.
Aqueous solutions and
solvents have Raman
bands.
Second-order effects
from the spectrometer.
Scattered light off the
excitation wavelength.
Dirty cuvette.
Solid-sample holder in
sample compartment.
Dark count is divided by
low reference signal.
Stirring speed is too fast.
Stirring bar is too large;
light beam is striking it.
USB cable is improperly
connected.
7-2
sample by a factor of 10 or 100
and retry experiment.
Reduce slit settings.
Bad lamp: change xenon lamp.
Reduce slit settings.
Let lamp warm up 20 min before
use.
Check dark value to determine.
Filter sample, or let particles settle
before running scan.
Change excitation wavelength to
move Raman band away from
fluorescence peak, or run a blank
scan of the solvent and subtract it
from the fluorescence spectrum.
Use cut-on filters to eliminate 2
order peak.
Place bandpass filters in excita-
tion light path.
Decrease emission-spectrometer
slit widths.
Clean the cuvette as described in
Chapter 5.
Rotate the holder to prevent direct
scatter from entering the emission
spectrometer.
Use Dark Offset checkbox; retry
scan.
Use slower stirring speed.
Use a smaller stirring bar (availa-
ble from Bel-Art Products,
Pequannock, NJ).
Check USB cable's connection.
Troubleshooting
nd
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