What’s the wiring? How’s it connected? Here’s a quick schematic:

                |-------------
5v--------------|+
                |  solid state relay (Data Sheet SC842110)

             ---|-
             |  |-------------
             |
             |
             |
             | PIO
           |/
ctrl(DQ)---|         1 Wire Switch (Data Sheet DS2405)
           |\
             |
             |
gnd———-

Digital Input

This is the 1-wire digital input interface. It includes opto isolation coupled with selectable input voltages.

1-Wire digital output devices come in single channel and mutli channel packages. I have used inividual DS2406 devices for each of the four channels on the relay board .

I have progressed into assembly and got the I/O boards mounted on a back plate. I am currently writing a simple script that will control the fill drain solenoids. You can see the float switch attached. This has been hooked up to my controller now for 2 weeks and seems very stable. This unit will be fitted into my new tank which I am saving for and hope to get in July..

This setup has a couple of failsafe features….One of the four relays control the 24VDC power to the other three relays thus I have to explicitly turn on two relays to either open the drain valve or the fill valve. So if a 1wire digital output glitches ON nothing will happen. The other thing was the fact that I have installed a DIN rail mount relay( its the blue one) this insures that if either of the two float switches which are mounted in the tank detect high level it cuts power off to the fill valve

this is a test page with image