I need to control several valves with a single channel, since related plantings are physically too far apart to control with a single valve. I have Rachio v2 controllers with supplied transformers. Several channels already drive 2 valves, with no issues. I’m looking to add valves 3 and 4 in a couple of channels.
Does anyone here have experience with 3 or 4 valves per channel?
- I am aware of the limitations of water pressure - but the multiple valves I’m activating are watering a few trees with dripper loops, with a total of maybe 100 x 0.4gph drippers across 4 valves, which doesn’t even make a dent in the water pressure (it’s capable of running much much bigger channels on this pump).
- I know that I could just use multiple channels programmed the same, but I’m running out of channels. I’m also running out of time in the day (I’m often watering from 5am to 4pm) - since the drippers are so slow and channels only run sequentially.
- I know that I could use multiple controllers, but it’s rather non-trivial to have multiple controllers coordinate to turn on the master pump valve. Also I have limited wiring in the garden, so I don’t have enough wires to run 30 or 40 channels (I have 3 cables x 7 wires that gives me 16 channels + common + master + 2 for the water meter + 1 spare).
The details:
I have a master valve that controls a relay that operates a tank pump, which takes 400mA inrush, 200mA steady state. I am using Rainbird CP075 valves which draw about 200mA inrush, 160mA steady state.
I read that the transformers are rated to 1A, which I interpret as having capability for 200mA for the master steady state + 4 x 200ma for 4 valves starting simultaneously. Empirically, I have tested master and 4 valves at once, and the transformer voltage doesn’t drop appreciably (still above 24VAC), and the transformer doesn’t get warm.
I read that Rachio’s switches are rated for 2 valves simultaneously. I have tested 3, and had no problems. I have (accidentally) tested the Rachio with a shorted channel, and note that it shuts down and sends me an email.
I am concerned that at three or four valves, the Rachio may intermittently think it has a short circuit and not reliably operate the channels with more than 2 valves at once.
The alternative is to use a bigger transformer, and use the Rachio to drive relays that are rated to as many valves as I want to drive. Does anyone have experience with using relays such as “Omron G2R-1-E”, or perhaps a rail-mount set like “DIN Rail Mount AC/DC 24V control 16 SPDT 16Amp Pluggable Power Relay Module, G2R-1-E”?