16
Properly connect the pH electrode and wire the separate ground probe
(if used) to the controller, then plug the meter to the mains.
It is recommended to perform calibration at a temperature similar to
that of the sample to be monitored.
Use a Checktemp (or another accurate thermom-
eter) as reference for temperature.
Remove the electrode protective cap.
During calibration, move the electrode and the
separate ground probe (if in use) together from
one buffer to the next.
If no separate ground probe is used, make sure
that the Reference and the Matching Pin terminals
are shorted.
If the pH electrode incorporates a ground probe/matching pin
(as for example HI1003/3), remove the jumper.
Set the SET/READ switch to “READ” position.
OFFSET ADJUSTMENT:
• Rinse the electrode (and ground probe) with
pH7.01 solution (
HI7007
), then immerse the
tip(s) in pH7.01 buffer. An immersion level
of about 4 cm (1.5”) is recommended.
• Place the Checktemp thermometer in the buffer solution. Adjust
the knob to show the same temperature as that measured by the
Checktemp and make sure the selector switch is in the MTC position.
pH CALIBRATION (HI9910 and HI9911)
