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11-2. Replacement of Sensor Unit
WARNING
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Be sure to turn OFF the indicator unit or signal converter before replacing a sensor unit.
Otherwise, they may become a source of ignition.
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Before turning ON the power supply to the Detector, make sure that the sensor and
sensor connector are connected properly.
CAUTION
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The external contact may operate when replacing the sensor unit if the sensor output is
not stable. Release the interlocks of the external devices if needed.
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Replace the oxygen sensor (model: OS-3M-G) once a year.
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The effective storage period of oxygen sensors for replacement is one month from the
time of manufacture. Be sure to use the sensors before the end of their usable period.
(The year and month of manufacture are given on the oxygen sensor package.)
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The oxygen sensor has positive and negative polarity.
Be sure to check the polarity
when replacing the sensor.
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When setting the oxygen sensor, make sure that the sensor pins do not damage the
sensor socket, which may result in a loose connection.
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Make sure that no dirt or dust is trapped in the sintered wire mesh of the sensor casing,
and install the sensor only after cleaning the wire mesh.
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Be sure to handle the sensor unit with care. Do not drop or throw the sensor unit.
Otherwise, the sensor wire may be disconnected or a sensor failure may result.
MEMO
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Return the used sensor to New Cosmos.
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After replacing the sensor, stabilize the sensor by turning it ON for approx. 1 minute, and
then perform the span adjustment.
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To adjust the gas concentration after replacing the sensor, always perform the span rough
adjustment first, followed by the 21.0 vol% adjustment.
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If an error is displayed, refer to 10. Trouble Alarm.
