Sommer GmbH
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9.5. Tables
9.5.1.
Minimum mixture length for the conductivity
measurement
Rule of thumb: L
≈ 50 ∙ b
L … minimum mixture distance; b … width of the river
river width
length of the mixture distance [m]
[m]
little turbulent
very turbulent
1
75
50
2
150
100
5
300
250
10
500
300
For limits with dilution of salt and other continuative information we recommend the book
MORGENSCHWEIS, G. (2010): Hydrometrie. 2010. XIV, 582 pp., Springer
9.5.2.
Salt requirement
To estimate the necessary salt requirement, first the amount of discharge has to be estimated. With short
mixture lengths and low background conductivity
normally 5 kg for an estimated discharge of 1000
liters/s are sufficient (rule of thumb)
.
With high background conductivities the notice of following table can increase the quality of the
measurement result:
Salt requirement [kg]
Estimated
discharge [l/s]
< 250 µS/cm
< 500 µS/cm
<1000 µS/cm
≥ 1000µS/cm
50
0,25
0,5
1
2
100
0,5
1
2
4
200
1
2
4
8
500
2,5
5
10
20
800
4
8
16
32
1000
5
10
20
40
Table: Salt amount in kg in dependence of the base conductance and the estimated discharge
