Waters Xevo TQ-S Operator's, Overview And Maintenance Manual page 71

The combined APPI/APCI source enclosure:
To prevent damage to the corona pin and lamp assembly,
Caution:
ensure that the lamp assembly does not touch the corona pin when the
source enclosure door is closed.
The UV lamp, which you ignite via a control in the MassLynx software Tune
window, provides a constant photon output. You vary the intensity of incident
radiation upon the sample molecules by adjusting the distance between the
UV lamp and probe tip.
Combined APPI/APCI source
APPI lamp drive assembly
February 28, 2014, 715002212 Rev. C
.
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