Hanna Instruments pH 300, Instruction Manual, Page: 21 / 57

41 40
pH VALUES AT VARIOUS
TEMPERATURE
The calibration buffer solutions are effected
by temperature changes to a lesser degree
than normal solutions.
When manually entering the calibration val-
ues (see program #2 for pH302) refer to the
following chart.
TEMP pH VALUES
°C °F 1.68 4.01 6.86 7.01 9.18 10.01
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
32
41
50
59
68
77
86
95
104
113
122
131
140
149
158
4.01
4.00
4.00
4.00
4.00
4.01
4.02
4.03
4.04
4.05
4.06
4.07
4.09
4.11
4.12
6.98
6.95
6.92
6.90
6.88
6.86
6.85
6.84
6.84
6.83
6.83
6.84
6.84
6.85
6.85
7.13
7.10
7.07
7.04
7.03
7.01
7.00
6.99
6.98
6.98
6.98
6.98
6.98
6.99
6.99
9.46
9.39
9.33
9.27
9.22
9.18
9.14
9.10
9.07
9.04
9.01
8.99
8.97
8.95
8.93
10.32
10.24
10.18
10.12
10.06
10.01
9.96
9.92
9.88
9.85
9.82
9.79
9.77
9.76
9.75
When using automatic calibration, the appro-
priate value will be displayed.
For instance, if the buffer temperature is at
25°C, the display will show "pH
4.01
" or
"
7.01
" or "
10.01
".
If the buffer temperature is at 20°C, the dis-
play will show "pH
4.00
"/"
7.03
"/"
10.06
".
If the buffer temperature is at 50°C, the dis-
play will show pH "
4.06
"/"
6.98
"/"
9.82
".
1.67
1.67
1.67
1.67
1.68
1.68
1.68
1.69
1.69
1.70
1.71
1.72
1.72
1.73
1.74
CALIBRATION WITH MANUAL TEMPERA-
TURE COMPENSATION
If for some reason the temperature probe is
defective, or it is required to calibrate with
manual temperature compensation, follow the
procedure below:
• Unplug the temperature probe from the
meter.
• Note the temperature of the
buffer solutions with a
ChecktempC or a glass
thermometer with a resolu-
tion of 0.1°C.
• For pH300 and pH301 only
Use UP or DOWN to
manually adjust the
display reading to the
value of the reference
thermometer (e.g.
20°C). The value will
be displayed on the
secondary LCD and
"°C" symbol will
flash.
•
For pH302 only
Press the +/- key (for eventual negative
figures) followed by the noted temperature
on the numeric keypad (e.g. 20°C) and
ENTER. The value will be displayed on
the secondary LCD and "°C" symbol will
be flashing.
• Follow the calibration procedure as for pH
calibration with temperature probe con-
nected (see page 29).
°C
°C °C
°C
0 2
°C
ENTER/