SpectraPure
®
SpectraPure
®
Inc
.
Fax 480.894.6109 Fax us toll-free 1.877.527.7873
[email protected] www.spectrapure.com
11
RO MEMBRANE DIAGNOSTICS:
In order to accurately determine the condition and performance of the
RO Membrane, a conductivity tester capable of reading the tap water
conductivity (or TDS) and the product water conductivity (or TDS) would
typically be required.
You may also use an alkalinity test kit (on softened water sources) or a
hardness test kit (on non-softened water sources).
Note: All water sources are different and are subject to changes in
conductivity from season to season which could affect the TDS
reading depending on the time of the year. For this reason, we
recommend the use of a conductivity (TDS) tester in order to determine
the most accurate measurement for determining the condition of the
RO membrane.
TESTING THE QUALITY OF THE MEMBRANE:
The performance of a RO membrane is measured by its ability to reject
salts or TDS (Total Dissolved Solids). This procedure will require a TDS
Meter. SpectraPure offers several models:
ELIM-MTR-TDS-EZ
HM Digital Hand-held TDS Meter
ELIM-MTR-TDS-DM1
HM Digital InLine Dual Probe TDS Meter
Procedure:
1. Measure tap water TDS. (Call it X)
2. Run the system for 15-20 minutes.
3. Rinse test instrument cell 2-3 times with RO water.
4. Measure RO water TDS directly from the blue product water line.
(Call it Y).
5. Subtract RO water TDS from tap water TDS. (X - Y)
6. Divide this quantity by tap water TDS. (X - Y) ÷ X
7. Rejection = [(X - Y) ÷ X ] ×100
TDS in the above procedure is measured in ppm or mg/l.
Important: Test the quality of the membrane once every 6 months.
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