Thermo Scientific 074114, Руководство оператора

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4 • Troubleshooting
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Absorbance in the reference wavelength
Sample absorbance in the selected reference wavelength may cause excessive
baseline drift. Select a reference wavelength and reference bandwidth in an
area of the spectrum where little absorption occurs (see
“Reference
Bandwidth” on page 51 ).
Thermo Fisher Scientific recommends selecting a reference wavelength (i.e.,
active reference mode) for gradient analyses and turning off the reference
wavelength for isocratic analyses in a laboratory with a stable ambient
temperature (see
“Reference Wavelength” on page 48 ).
4.7 Deuterium Lamp Intensity Reading Too Low
•
Light signal is not reaching the data processor
Check that at least one lamp is turned on. (When a lamp is on, the
corresponding LED (
DEUTERIUM – UV
or
TUNGSTEN – VIS
) is lighted.) If
necessary, turn on one of the lamps from Chromeleon or the TTL input.
•
Low light throughput
1. Remove the cell from the optical bench (see Section 5.4 ).
2. Check the deuterium lamp intensity:
a. Open the Chromeleon 7 Command window (see page 31 ) or the
Chromeleon 6.8 Commands dialog box (see page 32 ).
b. Select UV , and then select LampIntensity .
If the lamp intensity reading is above 10 million counts for a standard or
semi-preparative cell
or above 3 million counts for a semi-micro cell,
follow these steps:
a. Open the Chromeleon 7 Command window (see page 31 ) or the
Chromeleon 6.8 Commands dialog box (see page 32 ).
b. Select UV , and then select UV_Calibration .
c. Execute the Intensity command to calibrate the lamp intensity.
d. Execute the Autozero command to run the autozero routine.
e. If no error message is displayed, flush the cell with the mobile
phase for the application and/or clean the cell as instructed in
Section 5.2 .