Ametek Thermox CEM O2/TM, Руководство пользователя

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3-4 | Thermox CEM O2/TM
Sample Gas Requirements/Connection
Figure 3-1 shows the inlet and outlet ports on the CEM O2/TM sensor. The
sample gas should be clean and dry. If the sample contains any condens-
ing moisture, the entire sample line should be heat traced.
The sensor may operate at a steady internal pressure up to 20” WC (5
kPa). Outlet restrictions that raise the pressure beyond this level may
cause false or unstable readings. Use calibration gases at 1.0 L/min (2
SCFH).. The maximum sample temperature is 200°C (392°F).
Calibration Setup
Figure 3-1 shows the location of the inlet port on the CEM O2/TM sensor.
When calibrating your system, you will connect calibration gases up-
stream of this inlet port.
Required Calibration Gases and Tubing
Use calibration gases at 1.0 L/min (2 SCFH). Also be sure that you use the
same flow rate for calibrations and daily operations.
Span gas - Minimum one decade above zero gas (10 times greater). For
example, if zero gas is 1.0%, span gas must be 10% or higher. If zero gas is
0.1%, span gas must be 1% or higher.
Zero gas - from 0.1 ppm to 10% O
2
, balance N
2
Always use tubing that is free of oil and dirt.
Manual Calibration Connections
If you ordered a remote calibration unit, proceed to the “Remote Cali-
bration Unit Mechanical Installation” section below. If you don’t have a
remote calibration unit, we recommend that you insert a control valve be-
fore the inlet port of the sensor (Figure 3-1 shows the location of the sen-
sor gas inlet). Using this valve, you can easily switch between introducing
the sample and calibration gases to the CEM O2/TM sensor as shown in
the example on Figure 3-2 . You can either use the Series 2000 control unit
remote calibration signals or your own calibration initiation sequence to
control this valve. See the “Customer Supplied Remote Calibration Initia-
tion” section at the end of this section for help on how to use Series 2000
calibration signals to control calibrations.