Auto Pilot Voltage Levels

[Steve456]

This week I had to add salt to the pool because my salt level had fallen to 2,800 ppm. I increased the salt level to 3,400 ppm. I noticed that the reported voltage had changed. At a salt level of 2,800 the control unit reported 24 volts. At a salt level of 3,400 the control unit reported 22 volts. The amperage was the same at 6.5 amps. [Level 2]

An increase in salt would increase the conductivity of the water. Does the control unit reduce the voltage in order to maintain a constant 6.5 amps? Is there an advantage of operating the SWG at the lower voltage level?

 

[JasonLion]

Correct, the control unit varies the voltage to maintain a constant current, and thus a constant amount of chlorine produced.

With AutoPilot units, there is no advantage to higher or lower salt levels as long as you don't go below the lower limit (around 2,500). That is not true of most other brands, which care more about the salt level.

 

[Poolsean]

well, the higher salt level does allow the lower voltage, which also lets the unit run cooler, so there are some advantages. The amount of chlorine produced though, will be the same.

 

[JamesW]

well, the higher salt level does allow the lower voltage, which also lets the unit run cooler, so there are some advantages. The amount of chlorine produced though, will be the same.

I would think that the rate of chlorine produced would be related to the power used. If the current is the same but at a lower voltage, then the power usage should be lower and therefore, less chlorine should be produced?

 

[JasonLion]

Chlorine production is proportional to the number of electrons moving through the cell, which is what current is measuring/describing.