Yokogawa Multi Channel Oxygen Analyzer System ZR22/AV550G - Manual (Page 220)

IM 11M12D01-01E 12-10
4) Check whether the deterioration of or damage to the sensor assembly that caused the
alarm, has occurred suddenly during the current calibration by following the proce-
dure below.
a. Call up the Detailed Data display.
b. Use the Page Scroll key to check Calibration Data (Figure 12.9). The span and zero
correction factors of the last ten calibration can be checked here. By checking these data,
whether the sensor deterioration has occurred suddenly or gradually can be determined.
F03-cE.EPS
Ch1
Cell voltage: 0 . 9 mV
Thermo voltage: 2 9 . 4 mV
C.J.resistance: 1 1 7 0 . 2
⍀
Cell temperature: 7 5 0 Њ C
C.J.temperature: 4 3 Њ C
Warmup Hold
Fm-5E.EPS
Ch1
Calibration data:
1. 2 4 Jun. 2 0 0 4 1 2 : 0 1
Span gas ratio: 0 . 1 %
Zero gas ratio: 1 0 1 . 3 %
2. 0 0 0 0 2 0 0 0 0 0 : 0 0
Span gas ratio: 0 . 0 %
Zero gas ratio: 0 . 0 %
Warmup Hold
Figure 12.8 Detailed Data Display Figure 12.9 Calibration History
5) If the sensor assembly has deteriorated suddenly, the check valve that prevents
moisture in the furnace from entering into the calibration pipes may have malfunc-
tioned. If the furnace gas flows into calibration lines, the gas is cooled and thus
condensation develops and accumulates in the pipe. During calibration the conden-
sate is carried with the calibration gas and blow onto the sensor assembly, whereby
the cell is cooled quickly. This results in the failed sensor assembly.
6) If the sensor assembly has deteriorated gradually, check the condition of the sensor
assembly following the procedure below.
a. Use the Page Scroll key to check Cell Resistance. It should be 200
⍀ or less if the cell
(sensor) is new. On the other hand, if the cell (sensor) is approaching the end of its
service life, it will be 3 to 10 k
⍀.
b. Use the Page Scroll key to check Cell Robustness. It should say "Life > 1 year" if the
cell (sensor) is in good condition.
Fm-6E.EPS
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
⍀
Next cal date: 0 0 0 0 2 0 0 0
Warmup Hold
Figure 12.10 Detailed Data Display (Cell Robustness)