Thermo Scientific Accela PDA, Руководство по оборудованию

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5
ChromQuest Diagnostics for the PDA Detector
Controlling the Lamps from the ChromQuest Data System
Thermo Scientific Accela PDA Detector Hardware Manual 63
Controlling the Lamps from the ChromQuest Data System
From the ChromQuest data system, you can turn the lamps on or off and view the lamp’s
usage hours from the Accela PDA page of the Instrument Status window or from the Lamps
page of the Accela PDA Diagnostics dialog box.
The PDA detector keeps track of the number of hours each lamp has been operating. The
deuterium lamp has a lifetime of approximately 2000 hours and the tungsten lamp has a
lifetime of approximately 2500 hours. The useful lamp lifetime of the deuterium lamp
depends on the acceptable level of detector noise for your application (see
“Lamp Lifetime
and Detector Noise” on page 5 ).
As lamps age, they emit less light, which results in increased baseline noise. If the noise level of
your detector signal is unacceptable and cleaning the LightPipe flowcell does not help, use the
diagnostic features of the software to determine the cause of the problem. If light output
becomes too low and adjusting the attenuators as described in
“Adjusting the Light
Throughput with the ChromQuest Data System” on page 69 does not help, replace the lamps
(see “Replacing the Lamps” on page 89 ).
Y
To control the lamps from the Lamps page
1. Open the Accela PDA Diagnostics dialog box (see “Accessing the Direct Controls for the
Accela PDA Detector” on page 62 ).
2. Click the Lamps tab.
The Lamps page appears (see Figure 55 ).
Figure 55. Lamps page of the Accela PDA Diagnostics dialog box
Note The intensity of the deuterium lamp falls off very slightly over a period of time
after it is turned on. Plan to wait at least one hour for the lamp to stabilize after a cold
start before collecting data in the UV region.