Ametek Thermox Series 2000 WDG-IV, Руководство пользователя

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Overview
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1-7
Detectors
Combustibles
The Combustibles Detector is a dual element device. The elements differ
only in that one is coated with a catalyst. The catalyst causes oxidation
to occur at a lower-than-normal temperature. The temperature of the
catalyzed element changes as the combustible mixture burns. The tem-
perature change causes the resistance of the catalyzed element to change.
The resistance change is interpreted by the microprocessor and the corre-
sponding combustibles reading is displayed.
The Thermox catalytic combustibles detector will detect combustible
gases present in a sample. The sample must, however, contain enough
oxygen to fully burn the combustibles present. The combustibles detector
responds to all incompletely burned combustibles gases, such as CO and
H
2
. We recommend that you use an even mixture of CO and H
2
as the
combustibles component within your span gas, although you can also use
all CO if needed.
The combustibles span gas for calibration should be 60 to 80% (ppm
range) or 40 to 60% (percent ranges) of the selected combustibles recorder
output range.
Methane
The Methane Detector is a dual element device. The elements differ only
in that one is coated with a catalyst. The catalyst causes oxidation to occur
at a lower-than-normal temperature. The temperature of the catalyzed
element changes as the mixture burns. The temperature change causes
the resistance of the catalyzed element to change. The resistance change
is interpreted by the microprocessor and the corresponding reading is
displayed.
The Thermox catalytic methane detector will detect methane gases pres-
ent in a sample. The sample must, however, contain enough oxygen to
fully burn the methane present.
The methane span gas should be 2% CH
4
with 8 - 10% oxygen present in
the mixture.