Quote Originally Posted by mygoggie View Post

Just for interest sake, I am using two raspberry PI's with expansion boards to control things. One for the irrigation control and one for the logic and remote switching of the purification system.
Silly question... why 2 Rasberry and not just an Arduino?

What i understand of these units...the rasberry PI is a general purpose computer and the other (Arduino ) is a microcontroller?

I would be interested to see how you control this system.

Something else that is a consideration...control circuit voltage... i know with the large water treatment works...the control voltage is generally 24 VDC because of the PLC control.

However on smaller plants...machines etc where there is no PLC ...just relays...level... pressure and limit switch control...12/24/110 and 230 volts is common...in fact many of the machines i work on...sometimes have 3 or 4 different control voltages.