YOKOGAWA EXA DO402G, Руководство пользователя

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<8. Troubleshooting>
8-2
IM 12J05D02-01E
Table 8.1 Countermeasures in the case of failure (Error) detection
Error
No.
Generation
Mode
Error Content and Causes Countermeasures
E1 AIR.CAL mode
H2O. CAL mode
Stability failure
Even after an hour has elapsed,
the measured value change does
not decrease within the set value
of (mg/L)
• Sensor temperature changes.
• Dissolved-oxygen of the
calibration solution changes.
• The value of A (mg/L) is not
suitable.
Eliminate the causes and press the
(NO) key to perform re calibration.
E H2O. CAL mode Zero point error failure
The zero point error exceeds the
set range
• Dirt sticks to the tip of the sensor.
• Membrane abnormality.
Electrolyte degradation.
Clean the sensor membrane,
sensor cap, and recalibrate. If the
error is detected again, replace
the electrolyte and the membrane,
sensor cap.
E3 AIR.CAL mode
H2O. CAL mode
MAN.CAL mode
Slope failure
The slope exceeds the range of 40
to 200 % of the theoretical value.
• Dirt sticks to the tip of the sensor.
• Membrane abnormality.
Electrolyte degradation.
Clean the sensor membrane,
sensor cap, and recalibrate. If the
error is detected again, replace
the electrolyte and the membrane.
Check that the connection between
sensor and sensor cable is fit,
and LED emission of the optical
dissolved-oxygen sensor.
When error occurred again,
replace the sensor cap, sensor
cable or sensor itself.
E4 Measuring mode Sensor membrane failure Replace membrane
Check for wet O-rings in the
membrane assembly or wet
sealing face.
Wipe off wet areas and dry out.
E7 All modes Measured temperature failure (too
high)
It exceeds 50.0 °C (122.0 °F).
• Measuring solution temperature
is high
• CODE 10 setting is not correct
• Sensor cable wiring failure
• Temperature sensor has failed
Examine the temperatures of the
measuring solution and sensor and
the CODE 10 setting
Examine the sensor cable
connection status.
If the temperature sensor fails
(abnormal resistance), replace the
sensor.
E8 All modes Measured temperature failure (too
low)
It falls below 0 °C (or 32.0 °F).
• Measuring solution temperature
is low
• CODE 10 setting is not correct
• Sensor cable wiring failure
• Temperature sensor has failed.
Examine the temperatures of the
measuring solution and sensor and
the CODE 10 setting.
Examine the sensor cable
connection status.
If the temperature sensor fails
(abnormal resistance), replace the
sensor.
E9 All modes Input current failure
It does not satisfy the following
equation: input current < 50 μA
for galvanic sensor < 500 nA for
polarographic sensor and optical
sensor
Examine the setting for CODE 01,
02
E10 All modes EEPROM writing failure
Electronic circuit failure
Turn off the power and then turn it
back on and check whether or not
the system returns to normal.
If the failure occurs again, contact
Yokogawa to request repair.
E12 All modes Abnormal measured value
The dissolved-oxygen value
(%sat.) exceeds
150 % (or value set in CODE 54)
Examine the setting for CODE 01,
02
10, 12 & 54.
Accurately perform calibration.
9th Edition: Aug. 05, 2015-00