2
Installation
Completing the Installation and Verifying Operation
Thermo Scientific
Accela PDA Detector Hardware Manual
25
Completing the Installation and Verifying Operation
The Accela PDA Detector is calibrated at the factory. During installation, a Thermo Fisher
Scientific field service engineer adjusts the light throughput and recalibrates the detector.
The PDA detector uses the holmium oxide spectrum to verify its wavelength accuracy.
A two-position filter wheel (see
) that is accessible from the front panel of the PDA
detector contains this calibration solution.
For optimal performance, recalibrate the PDA detector and adjust its attenuators as part of a
routine maintenance program and whenever you move the instrument, replace the LightPipe
flowcell, or replace a lamp.
Because the deuterium lamp emits less light with use, monitor the integrated light intensity of
the diodes as part of a routine maintenance program, and adjust the attenuators when you
notice an increase in baseline noise. Because the diode array scan rate affects the integrated
light intensity, you must also adjust the attenuators when you modify the PDA detector’s
configuration by changing the diode array scan rate (see
on
).
The tabs that control the position of the attenuators are located on the front panel of the PDA
detector (see
). To adjust the light throughput, you push the attenuator tabs up or
down as you view the light intensity from your data system. Pushing the left tab up or down
controls the light throughput from the deuterium (D2) lamp. Pushing the right tab up or
down controls the light throughput from the tungsten-halogen (W) lamp.
Figure 20.
Attenuator tabs and filter wheel
STANDARD FILTER WHEEL
1 : OPEN
2 : HOLMIUM OXIDE FILTER
1
Tungsten
attenuator tab
Deuterium
attenuator tab
Two-position filter wheel
with holmium oxide
