Thermo Finnigan SpectraSYSTEM UV6000LP, Справочное руководство

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January 2004 Thermo Electron 4-17
ACCESSING THE
ATTENUATORS
Use the following procedure to access the attenuators:
1. Remove the front cover by gently pulling out on the bottom of
the cover and lifting up.
NOTE: On some models of the UV6000LP the attenuators are located
on the front of the chassis and do not require removing the chassis to
adjust (see figure 4.9). If your detector has these front chassis
attenuators, after removing the inner bezel door in step 2 go directly to
step 8, it is not necessary to remove the LightPipe assembly.
2. Remove the inner bezel door and LightPipe assembly.
3. To access the attenuators, loosen the two captive 3/16” Phillips
head screws that secure the chassis in place. (These screws are
in a recessed location in the base of the detector as shown in
Figure 8.2.) The screws are spring loaded and will be retained
when loosened.
4. Slide the chassis out of the detector housing until the metal
lamp compartment cover is accessible from the right side of the
instrument.
5. Free the lamp compartment cover from the detector chassis by
pressing on the metal tab inside the chassis wall.
6. Remove the foam insulation located on top of the optical bench
assembly.
7. Loosen the attenuator locking screw, which is a small Phillips
head screw located in the center of the internal metal wall
separating the optical bench from the lamp compartment.
The attenuators can now be adjusted. There are two black tabs
attached to the attenuators. The longer tab (for front chassis
attentuator models, the tab on the left) is for the (D
2
) Deuterium
lamp attenuator , the shorter tab (for front chassis attentuator
models, the tab on the right) is for the (W) Tungsten - halogen
lamp attenuator. Pushing the attenuator tab slightly up or
toward the rear of the detector will increase light throughput.
Pulling the tab slightly down or toward the front of the detector
will decrease light throughput to prevent saturation of the diode
array.
8. Monitor the light intensity as you adjust the attenuators:
•
For Atlas, go to “Monitoring the Light Intensity from
Atlas”.
•
For ChromQuest, go to “Monitoring the Light Intensity
from ChromQuest”.