Appendix, 2 ph temperature dependency – KROHNE OPTISENS PH 8500 EN User Manual
Page 50
7
APPENDIX
50
OPTISENS PH 8500
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04/2012 - 4001927601 - MA OPTISENS PH 8500 R01 en
7.2 pH temperature dependency
The output from a pH-electrode varies with the temperature in a predictable way. The size of the
variation depends on both the temperature and the pH being measured.
At pH 7 and 25°C / 77°F the temperature error is zero. If temperature or pH changes the
temperature error is calculated using the following formula:
0.03 pH-difference / pH or 0.03 pH-difference / K
°
C
°
F
pH
pH
pH
pH
pH
pH
pH
pH
pH
pH
pH
pH
5
41
2.30
3.24
4.18
5.12
6.06
7.00
8.06
9.12
10.18 11.24 12.30 13.36
15
59
2.15
3.12
4.09
5.06
6.03
7.00
8.03
9.06
10.09 11.12 12.15 13.18
25
77
2.00
3.00
4.00
5.00
6.00
7.00
8.00
9.00
10.00 11.00 12.00 13.00
35
95
1.85
2.88
3.91
4.94
5.97
7.00
7.97
8.94
9.91
10.88 11.85 12.82
45
113
1.70
2.76
3.82
4.88
5.94
7.00
7.94
8.88
9.82
10.76 11.70 12.64
55
131
1.55
2.64
3.73
4.82
5.91
7.00
7.91
88.2
9.73
10.64 11.55 12.46
65
149
1.40
2.52
3.64
4.76
5.88
7.00
7.88
8.76
9.64
10.52 11.40 12.28
75
167
1.25
2.40
3.55
4.70
5.85
7.00
7.85
8.70
9.55
10.40 11.25 12.10
85
185
1.10
2.28
3.46
4.64
5.82
7.00
7.82
8.64
9.46
10.28 11.10 11.92
95
203
0.95
2.16
3.37
4.58
5.79
7.00
7.79
8.58
9.37
10.16 10.95 11.74
.book Page 50 Wednesday, July 4, 2012 9:52 AM