Appendix, 2 ph temperature dependency – KROHNE OPTISENS PH 8390 EN User Manual
Page 45
APPENDIX
7
45
OPTISENS PH 8390
www.krohne.com
03/2012 - 4001930601 MA OPTISENS PH 8390 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 45 Monday, March 19, 2012 1:52 PM