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conphil

Member
Jul 6, 2020
16
The Villages, FL
Originally intended pool to be "hands-off"... let the pros clean and maintain. Wrong! Too many issues!

I'm a retired engineer always trying to understand how and why things function. Have gone opposite extreme to "hands-on" and now want to know all the details. Pool chemistry complex and fascinating. SWG "principles of operation" very difficult to understand and manufacturer technical support offers only "boiler-plate" responses that offer no new information (from the available manuals).

This site appears to have experts willing to probe and users willing to share experiences... just what I want. Currently exploring what's already available; will soon be asking my own questions.
 
Thanks for being the first to feed back.... just getting to learn the ropes about forum communications. I had read the "ABC's..." a long time ago as a guest on the site, but I reviewed it again just now at your suggestion. The test kit has been overworked for the last 2 years when we first started having pool issues and chemicals are renewed regularly. FYI, I have at least 2 years of detailed history on a spreadsheet... some of it is even beginning to make sense!
 
The Hayward T-Cell uses 13 plates (blades). The 2 white wires go to the center plate and one black wire goes to each outer plate. This makes the box and cell work like a battery charger where the water between the plates is the batteries. Assuming 24 volts DC and 6 amps, it’s like there are 2 sets of (6) 4volt batteries in series being charged with the sets in parallel. The total amps are 6 amps x 6 cells or 3 amps x 12 cells (36 amps either way).

Amps are the measure of the flow of electrons. The amperage is directly proportional to the chlorine production and directly proportional to the salinity. On one side of a plate, a chloride ion loses an electron to become a chlorine radical and then combines with another chlorine radical to create chlorine gas. So, one electron, one chlorine radical produced.


Polarity indicates if power is being sent to the cell and in which direction. There are 13 titanium plates in the cell. The center plate is connected to a wire going to the power supply and the two outer plates are connected to two wires going to the power supply. Half the time the center plate is the negatively charged cathode creating hydrogen gas, and the outer plates are the positively charged anodes creating chlorine gas and half the time the polarity is reversed.

Anode 4Cl- -> 2Cl2.

Cathode 4H2O -> 2H2 + 4OH-

2Cl2 +2H2O -> 3H++ HOCl + OCl- + 2Cl-

HOCl + OCl-+ uv light -> O2 + H+ + 2Cl-

Following the process, we can see that there are 4H+and 4OH-created, which nets out to ph neutral.

The chlorine gas generated is very acidic and creates 3 hydrogen ions for every 4 hydroxide ions created.

As the hypochlorous acid is broken down by uv, 1 more hydrogen ion is created for a net neutral result.

Assuming that chlorine gain and loss are equal, there's no ph rise.

 
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Welcome to the forum!
Great decision to have a quality test kit all ready!
I suggest you read ABC's of Pool Water Chemistry.
Thanks for being the first to feed back.... just getting to learn the ropes about forum communications. I had read the "ABC's..." a long time ago as a guest on the site, but I reviewed it again just now at your suggestion. The test kit has been overworked for the last 2 years when we first started having pool issues and chemicals are renewed regularly. FYI, I have at least 2 years of detailed history on a spreadsheet... some of it is even beginning to make sense!
 
Welcome Conphil !! You found the right place. You are in good hands and can dive as deep as you'd like into the how's and why's.