YOKOGAWA ZR22G User Manual page 223

(6) Alarms 203 and 204: Span correction ratio high and low alarm
This error occurs when the span point correction rate exceeds the range of 0 ± 18% in automatic
calibration or semi-automatic calibration (see Section: "9.1.4
caused by the following:
• The span gas oxygen concentration does not match the span gas concentration value set in
"Setting calibration".
• The span gas flow rate is outside the specified flow rate (600 ± 60 ml/min).
• The sensor assembly is damaged and the cell electromotive force is abnormal.
<Searching for the cause of the error and remedy>
(3) Check the following and perform calibration again. If the condition is not correct, correct it.
1. When "Span Gas Concentration" is displayed in "Calibration Settings", is the set value
and the span gas concentration actually used matched?
2. Are calibration gas pipes constructed so that span gas does not leak?
(4) If no alarm was detected as a result of recalibration, it is probable that the calibration
condition was inappropriate as the cause of the alarm in the previous calibration. In this
case, no special remediation is required.
(5) If an alarm occurs again as a result of recalibration, the sensor assembly may be degraded
or damaged as the cause of the alarm. It must be replaced with a new cell (sensor), but do
the following before replacing.
It must be replaced with a new cell (sensor), but before replacement, follow the procedure of
(5) Alarm 201, 202: Zero correction ratio high and low alarm <Search for the cause of
the error and remedy> (3) to (6).
(7) Alarms 205 and 206: Cold junction temperature alarm
This error occurs when the cold junction temperature at the detector's terminal (terminal block
in the converter when /CJ option was chosen) drops below-25°C or exceeds 155°C. If "C.J.
Temperature" is indicated as 200°C or-50°C, the following may be considered.
• Breakage of the cold junction signal wire between the converter and the detector. Or, the
cable is not securely connected to the connection terminal.
• The cold junction signal is in the middle of wiring, or the + and-poles are short-circuited at
the connection terminal.
• Defective detector terminal cold junction temperature sensor
• Converter internal electrical circuit error
If the "C.J. Temperature" is higher than 150°C or lower than -20°C, the following may be
considered:
• The temperature of the detector terminal block is out of the operating temperature range
(-20°C to 150°C).
• Defective detector terminal cold junction temperature sensor
• Converter internal electrical circuit error
<Searching for the cause of the error and remedy>
Before proceeding with the operation below, investigate whether the terminal part of the detector
exceeds the operating temperature range. The operating temperature range depends on the
detector model. If it is exceeded, take measures to reduce the temperature, such as taking
measures to avoid receiving radiant heat.
(1) Disconnect the power supply to the converter.
(2) Remove the wires from terminals 5 and 6 of the detector and measure the resistance
between the terminals. If the resistance value deviates from the range of 1 to 1.6 kΩ, the
cold junction temperature sensor may be defective.
Replace the cold junction temperature sensor.
<12. Troubleshooting>
Compensation"). This may be
IM 11M12G01-02EN 1sh Edition : Mar. 25, 2021-00
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