24
MW806
Portable Meter
8. pH
8.1. PREPARATION
Up to a 5‑point calibration can be performed using 7 standard
buffers and 2 custom buffers (CB1 and CB2).
1. Prepare two clean beakers. One for rinsing and one for
calibration.
2. Pour small quantities of the selected buffer solution into each
beaker.
3. Remove the protective cap and rinse the probe with the buffer
solution for the first calibration point.
8.2. CALIBRATION
General Guidelines
For better accuracy, frequent calibrations are recommended.
The probe should be recalibrated at least once a week, or:
y
Whenever it is replaced
y
After testing aggressive samples
y
When high accuracy is required
y
When the calibration timeout has expired
Procedure
1-point Calibration
1. Place the probe tip approximately 4 cm (1 ½”) into the buffer
solution and stir gently.
Note: For a 2‑point calibration, use the pH 7.01 (pH 6.86 for NIST)
buffer first.
2. Press CAL/EDIT to enter Calibration mode. Buffer value and
“WAIT” message are displayed blinking. If required, use
the
keys to select a different buffer value.
ºC
ATC
7.01
pH
CAL
28.0
7.0 1 P H
7.49
W A I T
ACCEPT
ºC
ATC
7.01
pH
CAL
28.0
7.0 1 P H
7.02
3. When the reading is stable and close to the selected buffer,
the ACCEPT tag is displayed blinking. Press GLP/ACCEPT to
confirm calibration.
