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CAL
°C
READY
ATC
pH
CAL
CAL
HOLD
pH
ENT
4.3
pH Calibration
The pH Transmitter is capable of calibration of up to 2 points using USA or NIST pH
buffer standards. All new calibration values will automatically override the existing
calibration data. pH buffer values are referenced to 25
o
C. Ensure the measurement
mode is set to
pH
. (Refer Section 5.5 for switching measurement modes). All pH
buffer values have window of up to
±
1 pH tolerance during calibration. Calibration
error can be occurred if the measured pH value exceeds this window. If you wish to
abort the pH calibration, press
▲
and
▼
keys simultaneously and the pH
Transmitter reverts to pH measurement mode.
4.3.1
For USA Standard Buffer
Make sure that the pH Transmitter is set to accept USA standard buffer in the Setup
mode. (Refer Section 5.4 for Buffer Selection Settings) The factory default is USA
standard. It is recommended that you perform a 2-point calibration at room
temperature (25
o
C), starting with the first buffer at pH 7.00 followed by any other
buffer value (pH 4.01 or 10.01).
1-Point Calibration:
CAL
HOLD
CAL
pH
Y
READ
pH
HOLD
CAL
pH
mV
HOLD
MEAS
°C
Y
READ
ATC
pH
°C
CAL
ENT
•
To exit Calibration mode at any time press
▲
and
▼
keys simultaneously (Escape).
•
The calibration is always carried out in the units of
measurement (pH or mV), selected in setup mode
1
1
2
3
4
ENT
