I'm working on a home automation related project that needs some electrically operated solenoid valves. Eventually this may become a commercial niche product, but the annual run rate will be only a couple thousand units. Overall system cost is a significant factor, but there are a LOT of other significant specs to satisfy (including some rather convoluted requirements for operation from backup power sources).
I need an inexpensive solenoid valve to control water flow in a residential water system. The valves used in home sprinkler systems are inexpensive, but they require 24 VAC - which I would have to create from a lower, DC, voltage using some kind of power inverter. And, they pull a constant 3 - 5 watts when energized which adds up when you're driving several of the things.
I put a lot of investigation into the Orbit p/n 62035 that is used in their latest controllers powered from 3 AA-cells. (See the thread "Sprinkler Thoughts" on this Forum.) I would have to fit each one with some driver electronics to create very short-duration 17 volt, 4 amp, pulses. That's do-able, but doesn't help either schedule or budget. And, there's no way to tell (electrically) whether the valve is OPEN or CLOSED.
The "ideal" valve I'm looking for would not significantly restrict the flow in a 3/4" garden hose. It would operate from a DC voltage in the 10 - 15 volt range. I can live with a continuous operating power of 1 - 2 watts - but the perfect solution would be some kind of latching solenoid with an auxiliary contact to show whether it is OPEN or CLOSED.
Does anybody here have any suggestions?
Thanks,
Dale
