I have a 16 zone Rachio controller that controls my irrigation system. My system includes a master valve that the controller automatically turns on whenever any zone is activated, so that the main water supply piping in my system will be pressurized with water.
I am into smart home stuff, and also into computer automation through things like the Arduino microprocessor. I am considering tapping into my irrigation main water supply piping to some other things with the water. To do this, I would need to turn on the master water valve.
Turning on the master water valve is simple; all I need to do is to provide 24 volts AC to the master valve. But of course this is what the Rachio controller does, so I recognize that might cause some electrical interference problems that could damage the Rachio controller.
After doing some research, I see that there is an isolator available that is recommended for use when you need to have 2 or more controllers activating the same master valve. I believe that my situation is the same thing (me providing 24 volts AC to turn on the master valve), so therefore I need to use 2 isolators; one for the Rachio controller, and one for my home grown 24 volts AC application.
Do you agree?
Thanks in advance!
A couple of relays and a 120v/24VAC transformer should do the trick.
Each system (Rachio or Arduino) only drives the coil of the relay. When the relay is closed the common to the new transformer is part of the circuit. That way even if both relays are closed you’re isolated from the electronics themselves.
I’m not sure I’m following you. Are you saying that I really don’t need an isolator?
I’m not very knowledgeable about electronics, but it sounds as if you are discussing this from the standpoint of the master valve end (the coil in the valve that when given 24 VAC, causes the valve to open). But isn’t the issue that two different 24 VAC sources (one coming out of the Rachio, the other coming from a 24 VAC power supplied being controlled by the Arduino), the two 24 VAC sources could interreact in some bad way and harm the Rachio?
No worries
A relay would isolate the two system as each would only drive a coil. The coil closes the relay and connects a separate system entirely. I can draw up an example later but for now https://www.12voltplanet.co.uk/user/Simplified_relay_diagram_Lg.png
I see. I think. To see if I’m following you correctly, I drew up a more specific diagram (hopefully it will make it through this reply email)
It has 2 relays, one activated by the 24 VAC master valve output from the Rachio controller, and the other activated by an output from the Arduino. Since the 24 VAC that eventually activates the master valve always comes from the same external 24 VAC power supply, it then no longer matters which relay is turned on. It can be either one or both at the same time.
Correct?
Thanks SO MUCH for your help! I’m obviously an electronics newby.
I see. I think. To see if I’m following you correctly, I drew up a more specific diagram (hopefully it will make it through this reply email)
It has 2 relays, one activated by the 24 VAC master valve output from the Rachio controller, and the other activated by an output from the Arduino. Since the 24 VAC that eventually activates the master valve always comes from the same external 24 VAC power supply, it then no longer matters which relay is turned on. It can be either one or both at the same time.
Correct?
Thanks SO MUCH for your help! I’m obviously an electronics newby.
