Langelier Saturation Index (LSI) Calculated

Langelier Saturation Index (LSI) is a mathematical formula that is used to determine if the water will etch the pool walls or will promote scaling.

This calculated result requires the following items to complete the formula:

pH, Temperature, Calcium Hardness, Total Alkalinity, Total Dissolved Solids (TDS) and Cyanuric acid (if present).

THOR tracks pH and Temperature dynamically. If a conductivity or TDS sensor is installed (not typical) this will also be dynamically tracked. Calcium, Alkalinity, TDS and Cyanuric acid values must be entered manually  (note: if Cyanuric acid is not being used the default value is "0").

The system will track and log the LSI and change dynamically as the pH and temp change.  The input will use the values in the manual fields until such time as they are updated. 

One item to note,  if your THOR is managing two vessels, it is important that the correct pH and temp sensor is selected when setting up your configuration. 

See step by step images below on how to configure. 

Add the Input. 

Navigate to the Summary Page and select the EDIT button on the actions section of the newly added Calculated Input.

 

Select the appropriate Calculation

Complete the Manual Values. 

(These manual values can be updated at any time by selecting the action button  > EDIT  > enter the updated values > skip to last > save input)

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