Sample requirements – Hach-Lange PHC805 User Manual User Manual
Page 4
•
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.
•
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 standard. The display shows the buffer and the temperature corrected pH value
when the measurement is stable.
•
The calibration and sample measurement conditions must be as similar as possible
(e.g., the temperature of the solution, the stir procedure, the stir rate and the position
of the probe).
•
If a calibration error occurs, refer to
on page 12.
Calibration 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. Push Calibrate.
The display shows the
buffers that are
necessary for
calibration.
3. Prepare the fresh
buffers in separate
beakers or applicable
containers.
4. Rinse the probe
with deionized water.
Dry with a no-lint
cloth.
5. Put the probe in
the pH buffer solution
and stir lightly. Make
sure to fully put the
reference junction into
the standard.
6. Push Read. Wait
until the reading
stabilizes.
7. Do steps 4–6
again to collect the
minimum number of
calibration points
specified in the
calibration options.
8. Push Done to view
the calibration
summary.
Note: The display will
not show "Done" until
the minimum number
of calibration points is
collected.
9. Push Store to
accept the calibration
and go back to the
measurement mode.
Sample requirements
N O T I C E
Some probes are not compatible with specific sample types. Probe damage can occur.
•
Samples must be aqueous. The probe can also make measurements in partially
aqueous or some water-miscible solvents. Read the results with caution because the
full pH scale changes when the solvent system changes.
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