Dräger Multi-PID 2, Руководство пользователя

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Connecting Accessories
11.7 eV UV Lamp
General Information
The Multi-PID 2 is equipped with a standard 10.6 eV UV lamp. An
11.7 eV UV lamp (Part No. 83 18 317) is available for special applica-
tions.
Install this lamp as outlined in Removing and Replacing the UV Lamp
on page 80. When you install a UV lamp other than the standard
10.6 eV lamp, all the response factors become invalid. You must set
the response factor for the current cal memory to 1. Contact Dräger
Safety’s Applications Department for further information.
Limitations of Lithium Fluoride Lamp Window
This lamp is intended for special applications only. It is not suitable for
normal operation, due to limitations of the lamp window material.
The 11.7 eV lamp window material is lithium fluoride (LiF). LiF is com-
posed of two light elements which are easily disrupted within the cry-
stal lattice by the UV light generated by the lamp. Disruption of the
lattice causes the crystal to turn a yellowish color, and again perfor-
mance declines.
Unlike other lamp windows, LiF readily absorbs water from atmosphe-
ric humidity. When contaminated by moisture, the window loses its
ability to transmit UV light.
Using the 11.7 eV UV Lamp
With an 11.7 eV lamp installed, your instrument functions as a detec-
tor responding to compounds which ionize at 11.7 eV or less. The
11.7 eV lamp may be useful for detecting compounds not ionized by
the standard 10.6 eV lamp.
Due to the lamp window limitations, the lifetime of the 11.7 eV lamp is
restricted and it must be used sparingly according to the following
instructions.
NOTE:
Do not use the 11.7 eV lamp in conjunction with the dilution
probe.
WARNING:
Do not touch the lamp window or handle it near
water.