Troubleshooting - VWR DO220 Manuel D'instructions

Troubleshooting

Erroneous dissolved oxygen readings typically indicate a need to clean
the sensor cap, replace the sensor cap, and/or recalibrate the instrument.
First, clean the sensor cap following the instructions in the Maintenance
section and then perform a calibration. If erroneous readings persist,
inspect the sensor cap for damage (cracks, large scratches in paint or
dye layer), replace if necessary, enter new coefficients and then attempt
to recalibrate the instrument.
If the sensor cap is not damaged, try to rehydrate the sensor cap then
recalibrate.
If you are still getting erroneous dissolved oxygen readings, try replacing
the sensor cap, enter the new coefficients and then recalibrate. If
the erroneous readings continue, contact Technical Support to help
determine the next step.
Symptom
Instrument will not
turn on, the BAT
symbol displays
on the screen.
Temperature values
display Over or Undr
on Run screen.
Instrument will not
calibrate dissolved
oxygen; instrument
displays "err' in
calibration mode.
DO readings are
inaccurate.
1. Low battery voltage, replace batteries.
2. Batteries installed incorrectly,
check battery polarity.
3. Return system for service.
1. Sample temperature is less than 0° C or more
than +50°C. Increase or decrease the sample
temperature to bring within the allowable range.
2. Contact Tech Support. Possible temperature
sensor failure.
1. Press Mode to cancel the cal error message.
2. Verify calibration routine - correct
barometric pressure, salinity input,
and calibration environment.
3. Allow sufficient stabilization time for
dissolved oxygen and temperature.
4. Check sensor cap. Clean, rehydrate
or replace as necessary.
5. Contact Tech Support.
1. Verify temperature readings are accurate.
2. Sample temperature should be
between 0 and 45 ºC, the temperature
compensation range for DO mg/L.
3. DO sensor not properly calibrated,
recalibrate the sensor.
4. Check sensor cap. Clean, rehydrate or
replace as necessary. Recalibrate.
5. Contact Tech Support.
14
Possible Solution