Measurement – Hach-Lange PHC745 User Manual
Page 6
Measurement
Before measurement:
The probe must have the correct service-life time stamp. Set the date and the time in the meter before the probe is attached.
If the complete traceability is necessary, enter a sample ID and an operator ID before the measurement. Refer to the HQd
meter manual for more information.
A regular calibration is necessary for the best measurement accuracy (refer to
on page 4).
Prepare the probe for use (refer to
Measurement notes:
•
Data is automatically stored in the data log when Press to Read or Interval is
selected in the Measurement Mode. When Continuous is selected, data is only
stored when Store is pushed.
•
Air bubbles under the sensor tip can cause a slow response or an error in the
measurement. If there are bubbles under the sensor tip, carefully shake the probe to
remove the bubbles.
•
For the best stabilization time, condition the probe for several minutes in the sample
or in a solution comparable to the sample in terms of pH and ionic strength before the
initial sample measurement.
•
Do not put the probe on the bottom or sides of the container.
•
Make sure that the filling hole is open and above the sample solution level.
•
Use a laboratory stirrer or shake the probe from side to side in the solution to refresh
the reference junction.
•
The meter display shows "Stabilizing" and a progress bar as the probe stabilizes in
the sample. The display shows the lock icon when the measurement is stable.
•
If a measurement error occurs, refer to
on page 13.
Measurement procedure:
1. Connect the probe
to the meter. Make
sure that the cable
locking nut is correctly
connected to the
meter. Set the meter
to on.
2. Condition the
probe in the sample.
3. Rinse the probe
with deionized water
and then with the
sample. Dry with a
no-lint cloth.
4. Open the sleeve
junction. Put the
probe in the sample
and stir lightly. Make
sure to fully put the
reference junction into
the sample.
5. Push Read. Wait
until the reading
stabilizes.
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