Endress+Hauser SpectraSensors SS2100i-1, Обзорное руководство

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SS2100i-1 and SS2100i-2 Analyzer
4
–
2 4900002288 rev. B 1-13-21
Setting the K
p
value
The system constant K
p
is determined at the factory when the analyzer is
calibrated. Using the system constant, the permeation device can be replaced
with another permeation device using a different permeation rate, and the
correct new permeation concentration will be calculated by the analyzer
software. The system constant K
p
will be consistent over the life of the analyzer
provided the temperature, sample flow rate and pressure of the system are not
changed from the factory settings. Should the K
p
value need to be reset, refer
to “Resetting the Sample Flow Rate and Recalculating the System
Constant Kp” on page 4-6.
Validation of Trace H
2
O Measurements Using
Permeation Devices
For trace moisture systems, SpectraSensors employs a patented G-CAL

permeation tube.
The permeation device is designed to continuously release a fixed rate of
moisture, approximately 2000 ng/min, at 50

C (122

F). Refer to Figure 4–1
on page 4–3 for a schematic diagram of the permeation tube. The moisture
released is continuously mixed with the dry process gas at 3000 sccm during
validation mode (refer to settings for Mode 7 in the Firmware Operator’s
Manual). This will result in a calibration mixture of C
p
in parts per million (ppm)
by volume, as long as return pressure is at atmospheric pressure.
Due to the required conditions, the sample flow pressure
regulator, flow control valve and needle valve are factory set and
should not be adjusted in the field. The flow components in the
sample system are marked with red tags and the message:
FACTORY SET - DO NOT FIELD ADJUST . The components have
been set to give the required flow rate at the conditions described
in the drawings provided with the analyzer. Changing any of these
settings voids the certification of the permeation system and
changes the measured concentration during validation.
The sample flow meters are NOT intended to be used for setting
the flows in the field. The measurement accuracy of the flow
meters is not sufficient to reproduce the factory flow rates in the
event the flow rates are inadvertently changed or require a
change.