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Table 2 Diagnostic messages (continued)
Message Meaning
Err
During start-up, this message indicates the instrument cannot complete the start-up tests
successfully. Refer to
on page 10. If the problem persists, contact your local
Hach Lange service representative for assistance.
During calibration, this message indicates that the partial pressure of gas is below the acceptable
range (<5 mbar), or that you have pressed a wrong key. Refer to
on page 17.
Bat
The batteries charge are too low for a correct operation of the instrument. Replace the batteries.
Continuous purge
It may be useful, particularly when seeing a
[Pur]
error message on your display, to view the purge
voltage of the TC sensor in a continuous purge mode. In this mode, there is no purge/measurement
cycle, as the purge gas is flowing through the sensor continuously.
To start continuous purge mode, put the instrument into standby, then hold down the
Down Arrow
button while switching the instrument back on again. The instrument displays
[Pur]
, followed by the
purge gas voltage. At 20-25°C, this voltage should be about 1.0V (± 200 mVolt) for CO
2
measurements.
To exit from continuous purge mode, put the instrument in standby, then switch back on again
without holding any keys.
Troubleshooting table
Symptom
Cause
Possible Solution
Unstable measurement
Degassing
Adjust sample flow rate
Flow chamber and/or membrane
not clean
Clean system
Sensor’s membrane not tight
smooth and wrinkle free
Replace membrane and recalibrate
Leaking solenoid valve
No gas bubbles should escape from the purge
gas outlet during measurement. If the solenoid
leaks (more than 1 bubble in 15 seconds) contact
your Hach Lange representative
An external power supply is used
but the power supply is not clean
Switch to battery power
Low readings
Sample flow rate too low
Check flow rate
Degassing
Adjust forcing gas and/or sample flow rate
Membrane is not at sample
temperature
Allow sample to flow past the membrane to make
sure the membrane is at sample temperature
before making measurements
Membrane not clean
Clean system
Incorrect solubility curve
Change solubility
Incorrect calibration
Recalibrate
High readings
Membrane is not at sample
temperature
Allow sample to flow past the membrane to make
sure the membrane is at sample temperature
before making measurements
Incorrect solubility curve
Change solubility
Incorrect calibration
Recalibrate
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