Omini o
perator’s
manual
version :19.04.17
15
Conductivity measurement procedure
7.4.2.1
General points
The global quantity of dissolved solids in water can be measured by the CONDUCTIVITY (expressed in
microsiemens per centimeter (µS / cm).
The conductivity measurement allows estimating the demineralization quality.
The relation between the TDS (total dissolved solids = total mineralization) and the conductivity is:
1 µS / cm ≈ 0, 4 mg / L of NaCl (sodium chloride)
7.4.2.2
Conductivity measurement operating method
1.
Let flowing the water to test 15 to 30 seconds.
2.
Remove the conductivity meter protection cap.
3.
Rince the protection cap and the conductivity meter probe with the water to test.
4.
Renew the operation 2 to 3 times.
5.
Fill protection cap of the conductivity meter with the water to test then plunge the
conductivity meter: read the measured value.
6.
Renew the operation 2 to 3 times; the retained value will be the last measurement one.
7.
Switch off the conductivity meter then put back the protection cap.
7.4.2.3
Purified water conductivity measurement « water purifier exit »
This conductivity measurement must be done weekly at the purified water outlet.
7.4.2.4
Conductivity measurement « membrane exit »
1.
Close the storage tank hand valve.
2.
Close the « ions exchange resins ENTRY » hand valve.
3.
Remove the plug on the outlet « TEST reverse osmosis membrane exit ».
4.
Open the « TEST reverse osmosis membrane exit » hand valve.
5.
Do the measurement
6.
Close the « TEST reverse osmosis membrane exit » hand valve.
7.
Reconnect the plug on the outlet and open the « ions exchange resins ENTRY » hand valve.
8.
Open the storage tank hand. The water purifier is again operational.
INTERPRETATION OF THE VALUE OF THE CONDUCTIVITY OF PURIFIED WATER
Conductivity <1 μS/cm
Class 1 water (according to ISO 3696)
Water of very good quality; no impact on the quality of the
analyzes
1 μS/cm <Conductivity <5 μS/cm
Class 2 water (according to ISO 3696)
If the desired water class is class 1, then change the resin
cartridge.
In any case, the resin cartridge will have to be changed soon
Conductivity> 5 μS/cm
Change the resin cartridge immediately
