Waters 2996, Operator'S Manual

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Replacing the Lamp 25
3
5. Replace the front cover.
6. Flush the flow cell (Section 3.1.1, Flushing the Flow Cell).
3.2 Replacing the Lamp
Replace the lamp in the 2996 Detector when either of the following conditions exists:
• The sampling rate requires an excessively long exposure time (more than
100 milliseconds).
• Intensity is low enough that sensitivity is not sufficient for your method.
Note: An improperly inserted flow cell could appear to be a problem with the lamp.
Note: If lamp intensity is low, but the lamp has not been used for 2000 hours, you may be
able to increase lamp intensity by cleaning the flow cell (Section 3.1, Flow Cell
Maintenance).
Absorbance by the mobile phase also affects the apparent lamp intensity. For example,
acetonitrile is more transparent than methanol at wavelengths less than 220 nm.
Caution: To avoid electrical hazards and exposure to UV light, turn off the power and
disconnect the power cord before you begin this procedure.
Caution: The lamp and housing are extremely hot. To avoid the possibility of contacting
hot surfaces, allow the lamp to cool for 15 minutes before you handle the lamp assembly
or surfaces close to the lamp.
STOP
Attention: Do not touch the lamp glass while unpacking or inserting the lamp. Touching
lamp glass damages the lamp and reduces life expectancy.
STOP
Attention: To prevent lamp glass contamination, use powder-free gloves when
removing or replacing the lamp.
Caution: The lamp may be very hot! Please allow it to cool for at least 15 minutes before
you attempt to remove it.