Calculating The Saturation Index; Tds Factor; Langelier Saturation Index Factors - Pentair INTELLICHLOR IC15 Guía De Instalación Y Usuario

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Calculating the Saturation Index

The saturation index is a formula that measures a solution ability to dissolve or deposit calcium carbonate and is
used as an indicator of the corroosivity of the solution and temperature. A well balanced water will have a
formula result ranging between -0.3 and +0.3 Outside this range, the pool water is considered out of balance,
potentially damaging pool equipment or scaling the IntelliChlor SCG.
Satura-
tion
Index
Cyanuric acid in the form of cyanurate ions contribute to alkalinity. Thus, a correction must be made to total
alkalinity. We subtract 1/3 of the cyanuric acid level from the reading obtained in the total alkalinity test.
Total Alkalinity - 1/3 Cyanuric Acid = Corrected Alkalinity
This correction can be considerable in established pools with high cyanuric acid levels; for example, at 100
ppm cyanuric acid, the correction amounts to 33 ppm (100 ÷ 3 = 33.3).

TDS Factor

(Factors shown below are based on the actual measured value for the particular parameter)
TDS Factor
<1000 12.10
1000 12.19
2000 12.29
3000 12.35
4000 12.41
5000 12.44

Langelier Saturation Index Factors

Note: Use the reading closest to your actual reading in choosing the factor.
Total alkalinity in this context refer to the total of carbonate and bicarbonate alkalinity. If cyanuric
acid is used, a correction factor must be used (see cyanuric acid Table 1 on page 13).
®
IntelliChlor Salt Chlorine Generator Installation and User's Guide
SI = pH + CHF + AF + TF - TDSF
pH as Calcium
Hardness
tested
Factor
The equation to calculate Si is:
Tempera-
Alkalinity
Factor ture
Factor
TDS
Factor