14
The TDS value in aqueous solutions is directly proportional to conduc‑
tivity. The ratio between the two parameters depends on the solution
and usually it is set to a factor of 0.5 (corresponding to a solution of
CaCO
3
). This means that 1 µS/cm is equal to 0.5 mg/L (ppm) of TDS.
For manual temperature compensation, refer to the following chart:
For instance, the TDS values of the calibration solutions at 25 °C are
1382 mg/L or 12.41 g/L when using HI7032 or HI7036, respectively.
At 20 °C, the values are 1251 mg/L or 11.24 g/L, respectively.
With the solutions at 30 °C, the values are 1515 mg/L or 13.61 g/L,
respectively.
ºC ºF
HI7032
mg/L (ppm)
HI7036
g/L (ppt)
0 32 758 6.82
5 41 876 7.88
10 50 999 8.99
15 59 1122 10.10
16 60.8 1148 10.33
17 62.6 1173 10.56
18 64.4 1200 10.78
19 66.2 1224 11.01
20 68 1251 11.24
21 69.8 1277 11.47
22 71.6 1303 11.71
23 73.4 1329 11.94
24 75.2 1358 12.18
25 77
1382 12.41
26 78.8 1408 12.65
27 80.6 1438 12.89
28 82.4 1461 13.13
29 84.2 1476 13.37
30 86 1515 13.61
31 87.8 1541 13.85
TDS VERSUS
TEMPERATURE CHART