User Guide

3938
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 pH301. 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
")