Galvanic Applied Sciences 943-TGS, Operation Manual

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Revision 1 72 6/27/2017
6.3 Changing the Anti-Solarant Solution
Radiation generated by the analyzer’s broadband UV Source Lamp in the deep UV region
(less than 200 nm) is capable of degrading the optical fibres. An optical fibre directly exposed
to the broadband source will develop an absorption band that reduces fibre transmittance at
wavelengths below 250 nm.
The degree of fibre degradation is a function of accumulated exposure time. The Anti-
Solarant Solution incorporated into the analyzer provides a high-pass optical filter with a
sharp cut-off region. The Anti-Solarant Solution blocks the deep UV radiation which is the
cause of the fibre degradation.
The Anti-Solarant Solution will eventually degrade to the point where it absorbs too much
energy causing the integration period to approach the maximum of 1000 ms. The frequency
of changing the Anti-Solarant Solution varies between one week and several months,
depending on the analyzer conditions. When the analyzer is exhibiting a loss of spectrometer
signal level (a high integration period required to reach 32,000 counts), the most probable
cause is degraded Anti-Solarant Solution.
Wear protective UV eye glasses at all times if the optical fibres are removed
while the UV Source is powered up.
The control cabinet door should NOT be opened while the analyzer is
energized UNLESS the area is known to be non-hazardous.
The Anti-Solarant Solution is to be changed only by authorized personnel.
The fluid holder may be warm. After the lamp is turned off, wait until the
solution cools before proceeding with this operation.
Refer to the Control Cabinet Components drawing while performing the following operation:
Always handle optical fibres carefully and avoid any contact with the end of
the fibre. Before proceeding with the following procedure, ensure that the
analyzer is Off Line and purged with zero gas.
a) Remove the
Source
optical fibre from the fluid holder bracket on the UV Lamp Supply.
Let the fibre hang freely and ensure that the end does not contacting anything.
It is suggested that a protective plastic cap is placed onto the end of the
fibre. This fibre is removed from the light path to protect it from unfiltered
exposure to the UV Source Lamp).
b) Loosen the light shield retaining screw on the bottom right-side of the fluid holder and
remove the light shield.