Hi everyone. We’re starting landscaping on a new house on a big lot with 39 zones of irrigation. I’d like to make sure the watering can occur offpeak from PGE (my (bankrupt) utility) to reduce the price of running the pump due to PGE’s rapacious pricing in the daytime. The irrigation is fed from well that can simultaneously pump enough water to support 5+ zones running at once.
When I do the math of what has to run in the summer to accomplish keeping things running offpeak, I need a minimum of 3 zones running at once, and 4 would make it really easy. I am planning to use 4 Rachio 3 12 zone units (from costco). I want to wire them up so that any one of the Rachios can turn the pump on. I explicitly want them to be able to all run at the same time, and the piping is set up to be able to make all that work.
The issue with using Rachio here is common pump control, and of the various smart irrigation controllers, only Rachio directs the use of the TSR isolators: https://www.transitionalsystems.com/isolator/ There are no examples on how to wire them for use with more than 2 controllers.
I am an engineer, but there are no schematics on the website to tell exactly what the isolator is doing. Obviously, if the 4 24VAC transfomers for the 4 Rachio 3’s are not wired from the same 120VAC circuit, or the hots and neutral get confused, you can have a big problem. In my case they will all be co-located, and fed from the same breaker. However, the safest bet might be to use a common much larger 24VAC power supply and feed all the Rachios from the same source. This prevents them from potentially causing a problem, and should result all the commons being tied together. It’s easy to find one of these and wire them together in this way (and neater too)
Does this resolve the need for the isolators? If needed, I can also wire up 4 relays to the master well relay in a way that the commons on the pump controls are not shared, but would like to know the best way to handle this configuration.
Hunter does make a large controller that can handle all these valves and simultaneous running of 4+ zones, but its a commercial unity and has no smarts, app control, etc…
Would love some advice from folks on solving this problem. I guess I could take one of the Rachios apart and see how the power is routed from the 24VAC line around the circuit boards, but I don’t think I should have to do that to figure out this configuration!