Teledyne 6400EH - Sulfur Dioxide Analyzer User Manual
Page 59
UV Fluorescence SO2 Analyzer
Troubleshooting
Teledyne
Analytical
Instruments
47
10.3.2.1
A
DJUSTING THE
UV
L
AMP
(P
EAKING THE
L
AMP
)
There are three ways in which ambient conditions can effect the
UV Lamp output and therefore the accuracy of the SO
2
concentration
measurement. These are:
Line Voltage Change: UV lamp energy is directly proportional to the
line voltage. This can be avoided by installing adequate AC Line
conditioning equipment such as a UPS/surge suppressor.
Lamp Aging - Over a period of months, the UV energy will show a
downward trend, usually 30% in the first 90 days, and then a slower rate,
until the end of useful life of the lamp. Periodically running the UV
lamp calibration routine (see Section 6.9.7) will compensate for this
until the lamp output becomes too low to function at all.
Lamp Positioning – The UV output level of the lamp is not even across
the entire length of the lamp. Some portions of the lamp shine slightly
more brightly than others. At the factory the position of the UV lamp is
adjusted to optimize the amount of UV light shining through the UV
filter/lens and into the reaction cell. Changes to the physical alignment
of the lamp can affect the analyzers ability to accurately measure SO
2
.
Figure 10-3: Shutter Assembly - Exploded View