ATO Cycling too much

[Hahnmeister]

Those suggestions may work for a Pico system but for anything of size its not going to solve anything.

Do you mean my suggestions? I would say they are good for up to about a 500g system. How big of a cup do you need?

 

[blurry]

having two switches wired together with the backup above the other for redundency is very preferred (if one sticks in the full position the other will act as the float switch)

Easiest way to ATO is with a controller: set to have a set timer run for X seconds when activated. I run a maxijet1200 for 30 seconds when the ATO is tripped, and force it off for 9:30 seconds after. This has a few benefits - (1) the RODI is connected to my topoff, so it isn't constantly being hammered on (2) even if all goes wrong I only add 30 seconds of water every 10 minutes so the flooding is reduced.

Great ideas in this thread. Combine them all and you get this:

picture of dual switch using conventional float switches:

 

[AZDesertRat]

That is basically what the UPLC-II from Spectrapure is but it adds adjustability as well as redundancy. read the manual here:
http://www.spectrapure.com/manuals/PRINTER_FRIENDLY/UPLC-II-MANUAL.pdf