The Uv Light Path; Uv Lamp Shutter & Pmt Offset - Teledyne T102 Operation Manual

THEORY OF OPERATION

10.2. The UV Light Path

10.2.1. UV Lamp Shutter & PMT Offset
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The Teledyne API UV Fluorescence SO
these circumstances.
The light path is very short (
•
A reference detector measures the intensity of the available excitation UV
•
light and is used to remove effects of lamp drift(
The temperature of the sample gas is measured and controlled via
•
heaters attached to the sample chamber so that the rate of decay (k) is
constant.
A special hydrocarbon scrubber removes the most common interfering
•
gases from the sample gas.
And finally, the design of the sample chamber reduces the effects of
•
stray light via its optical geometry and spectral filtering.
The net result is that any variation in UV fluorescence can be directly attributed to
changes in the concentration of SO
The following information is in addition to that contained in the UV Light Path section
in the T101 Manual - PN 07266.
Inherent in the operation of both the reference detector and the PMT are minor
electronic offsets. The degree of offset differs from detector to detector and from PMT
to PMT and can change over time as these components age.
To account for these offsets the T102 includes a shutter, located between the UV Lamp
and the source filter, that periodically cuts off the UV light from the sample chamber.
This happens every 30 minutes. The analyzer records the outputs of both the reference
detector and the PMT during this dark period and factors them into the SO
concentration calculation.
The reference detector offset is stored as and viewable via the front
•
panel as the test function DRK LMP.
The PMT offset is stored as and viewable via the front panel as the test
•
function DRK PMT
Teledyne API - T102/501 TRS, Addendum to T101 Operation Manual
Analyzer is specifically designed to create
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).
in the sample gas.
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07267B DCN6485
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