39
38
• Only when the read-
ing is stable (less
than ±0.03 variation
in a 10 seconds time
interval), the "
BUF
1
" in-
dicator will stop flash-
ing (after about 30
seconds) and the
"CFM" indicator will
blink.
• Press CFM to con-
firm the calibration.
If the reading is not
within 70% to 108%
of the buffer solution,
"WRONG
BUF
3
" and
"WRONG " will blink
alternately. If the
reading is close to
the selected buffer
(between 70 and
108%), the meter
stores the reading (and adjusts the 2
nd
slope point).
• The calibration process is ended with the
offset and the 1
st
and 2
nd
slope of the
meter calibrated.
Note: the meter will automatically skip the
buffer that was used for the first and
second calibration to avoid erroneous
calibration.
Note: during calibration, the sec-
ondary LCD displays the
selected buffer value. By
pressing RANGE the tem-
perature value can be also
displayed. This will allow
you to check the buffer temperature dur-
ing calibration.
CFM
CFM/
WRONG
WRONG
BUF
RANGE
Note: during calibration, the
secondary LCD dis-
plays the selected
buffer value. By press-
ing RANGE the tem-
perature value can be also displayed.
This will allow you to check the buffer
temperature during calibration.
THREE-POINT CALIBRATION (for pH301
only)
A three-point calibration (for the entire pH
range) can be performed with pH 301. These
are the selectable buffers:
1
st
buffer
2
nd
/3
rd
buffer
3
rd
/2
nd
buffer
(offset)
(1
st
slope)
(2
nd
slope):
pH 6.86
pH 1.68
pH 9.18
or 7.01
or 4.01
or 10.01
or 9.18
or 4.01
• Proceed as described for the
two-point calibration but do not
quit calibration by pressing
CAL at the end.
• After the second calibration
point is confirmed, immerse
the pH electrode into the
third buffer solution (e.g.
pH 10.01) and shake briefly.
Note: the electrode should
be submerged ap-
proximately 4 cm
(1½") into the solu-
tion. The temperature
probe should be lo-
cated as close as
possible to the
pH electrode.
•
Select the 3
rd
buffer
value on the secondary
display by pressing UP
or DOWN (e.g.”
10.01
”
).
RANGE
CAL
HI 7004
HI 7010
°C
°C
RANGE
4 cm
(1
½
")