Calibration – Hach-Lange PHC108 User Manual
Page 3
Calibration
Before calibration:
The probe must have the correct service-life time stamp. Set the date and the time in the meter before the probe is attached.
It is not necessary to calibrate again if a calibrated probe is moved from one HQd meter to another. Make sure that the
additional meter is configured to use the same calibration options.
To view the calibration data, push
, then select View Probe Data>View Current Calibration.
If two probes are connected, push the UP or DOWN arrow to change to the single display mode to show the Calibrate option
(available only on HQ40d and HQ440d meters).
Prepare the probe for use (refer to
Calibration notes:
•
Use buffers that are two pH units apart.
•
Select additional standard sets with the minimum number of calibration points in the
Calibration Options. For a two-point calibration, select: one buffer with a pH above
and one buffer with a pH below the sample pH. For a one-point calibration, select the
buffer nearest to the sample pH.
•
The calibration is recorded in the probe and the data log. Send the calibration to a
PC, a printer or a flash memory stick if connected.
•
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 10.
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.
3