Ametek Thermox WDG-V, User Manual

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System Overview
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2-1
SYSTEM OVERVIEW
Sensor Operations
Designed for fast response in a wide range of flue gas applications, the
sensor mounts directly on the combustion process to provide continuous
measurement of oxygen, or oxygen and combustibles, or oxygen, combus-
tibles and methane.
A sample is drawn from the process stream by means of an air-operated
aspirator and is immediately returned to the process. A portion of this
gas rises past the oxygen measuring cell and combustibles detector and
returns to the primary loop. All sample wetted parts are heated to 200 °C
maintain the sample above the dewpoint of the gas.
Observe these cautions when working on the sensor:
Do not turn on the aspirator until the analyzer has been turned on
and is hot - preferably 24 hours. Also, if you turn off the analyzer or
the process is shut down, turn off the aspirator air to avoid plugging
problems!
Remove AC power from the sensor and allow the sensor to cool for at
least one hour before performing any maintenance or troubleshooting
activities.
The outside of the sensor cover and all sensor assembly components
are hot during normal operation (up to 500°F, 260°C inside the cover).
Allow sensor components to cool for at least an hour before working
inside the sensor. Use caution and wear appropriate gloves when han-
dling components or when touching the sensor cover!
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