YOKOGAWA ZR22S, Руководство пользователя

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<12. Troubleshooting>
12-8
Alarm 7: Span Calibration Coefficient (Correction Ratio) Alarm
In automatic or semi-automatic calibration, this alarm is generated when the span correction ratio
is out of the range of 0±18% (refer to Subsection 9.1.3, Compensation).
The following are suspected as the cause:
(1) The oxygen concentration of the span gas does not agree with the value of the span gas set
in Calibration setup.
(2) The flow of the span gas is out of the specified flow value (600±60 ml/min).
(3) The sensor assembly is damaged and the cell voltage is abnormal.
<Locating cause of alarm, and countermeasures>
(1) Confirm the following and carry out calibration again: If the items are not within their proper
states, correct them.
a. If the display “Span gas conc” is selected in Calibration setup, the set point should agree
with the concentration of span gas actually used.
b. The calibration gas tubing should be constructed so that the span gas does not leak.
(2) If no alarm is generated as a result of carrying out re-calibration, it is suspected that
improper calibration conditions were the cause of the alarm in the preceding calibration.
In this case, no specific restoration is necessary.
(3) If an alarm is generated again as a result of carrying out re-calibration, deterioration of or
damage to the sensor assembly is suspected as the cause of the alarm. Replacement
of the sensor (cell) with a new one is necessary. However, before replacement, carry
out the procedure described in step (3) and later of <Location cause of alarm and
countermeasures> in Subsection 12.2.2, Alarm 6: Zero Calibration Coefficient (Correction
Ratio) Alarm.
Alarm 8: EMF Stabilization Time-up Alarm
This alarm is generated if the sensor (cell) voltage has not stabilized even after the calibration
time is up for the reason that the calibration gas (zero gas or span gas) has not filled the sensor
assembly of the detector.
The following are suspected as the cause:
(1) The flow of the calibration gas is less than normal (a specified flow of 600±60 ml/min).
(2) The length or thickness of the calibration gas tubing has been changed (lengthened or
thickened).
(3) The sample gas flows toward the tip of the probe.
(4) The sensor (cell) response has deteriorated.
<Locating cause of alarm, and countermeasures>
(1) Carry out calibration by passing the calibration gas at the specified flow (600±60 ml/min)
after checking that there is no leakage in the tubing.
(2) If calibration is carried out normally, perform a steady operation without changing the
conditions. If the error occurs again, check whether or not the reason is applicable to the
following and then replace the sensor assembly.
• A lot of dust and the like may be sticking to the tip of the detector probe. If dust is found,clean
the probe (see Subsection 11.1.1).
In addition, if an error occurs in calibration even after the sensor assembly is replaced, the
influence of sample gas flow may be suspected. Do not let the sample gas flow toward the
tip of the detector probe, for example, by changing the mounting position of the detector.
IM 11M13A01-02E