YOKOGAWA av550g, User Manual

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< 10. Other Functions >
10-1
IM 11M12D01-01E
10. Other Functions
10.1 Display
On the basic panel display, touch the Detailed data key to view detailed operational data (see Figure
10.1). On the detailed data display you can scroll up / down a page with the ▼ and ▲ keys, and you
can switch to another channel with the ◄ or ► key . A detailed data display has 12 pages (screens)
per channel. The following describes each data item.
F10-1-1E.ai
Ch1
Cell voltage: 0 . 9 mV
Thermo voltage: 2 9 . 4 mV
C.J.resistance: 1 1 7 0 . 2
Ω
Cell temperature: 7 5 0 °C
C.J.temperature: 4 3 °C
F10-1-2E.ai
Ch1
Span gas ratio: 0 .1 %
Zero gas ratio: 1 0 1 . 3 %
Response time: 0 s
Cell robustness: life> 1 year
Cell resistance: 1 1
Ω
Next cal date: 0 0 0 0 2 0 0 0
Figure 10.1 Detailed Data Display
10.1.1 Cell Voltage
The cell (sensor) voltage will be an index to determine the amount of degradation of the sensor.
The cell voltage corresponds to the oxygen concentration currently being measured. If the indicated
voltage approximates the ideal value (corresponding to the measured oxygen concentration), the
sensor will be assumed to be normal.
The ideal value of the cell voltage (E), when the oxygen concentration measurement temperature is
controlled at 750ºC, may be expressed mathematically by:
E = -50.74 log (Px/Pa) [mV]
where, Px: Oxygen concentration in the sample gas
Pa: Oxygen concentration in the reference gas, (21% O
2
)
Table 10.1 shows oxygen concentration versus cell voltage.
Table 10.1 Oxygen Concentration Vs. Cell Voltage, (cell temperature: 750 ° C)
%O
2
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9
mv 117.83 102.56 93.62 87.28 82.36 78.35 74.95 72.01 69.41
%O
2
1 2 3 4 5 6 7 8 9
mv 67.09 51.82 42.88 36.54 31.62 27.61 24.21 21.27 18.67
%O
2
10 21.0 30 40 50 60 70 80 90
mv 16.35 0 -7.86 -14.2 -19.2 -23.1 -26.5 -29.5 -32.1
%O
2
100
mv -34.4
T10.1E.ai
10.1.2 Thermocouple Voltage
The cell temperature is measured with a Type K (chromel-alumel) thermocouple. The thermocouple
cold junction is located in the detector terminal box. The cell temperature and the thermocouple
voltage (including the voltage corresponding to the cold junction temperature) are displayed.