I’m planning to make a water feature that has 5 programmable valves triggered by a proximity sensor through the particle photon, and I’ve found these to be my best option.
I’ve read a little into this thread which answered all my questions in regards to using 1 (and it requires snubber diodes, TIP120 Transistors, and 1K ohm resistors)
But if I am aiming to operate 5, and do so for 4 hours a day for many years to come (aiming for longetivity here) , Is that going to be possible? How will i power it?
Any ideas or opinions are welcome,
Thanks in advance,
Struggling University Student
How much power you need depends on how many of these solenoids with be drawing power at the same time. Could all five be on at once? Could all five conceivably turn on at the same instant?
At different times, there would be 5 operating at one time. Otherwise, there would be either 1,4, or none.
So to briefly answer the question, yes, all 5 at the same time. Is it possible? How to power them?
@daveforge, you may need to consider latching water valves like this one:
These only require power when they change states. If you battery power the whole thing, you will need to consider solar charging to maintain your batteries to run both the Photon and valves. Operating 5 valves simultaneously will require about 2.5A at 5V, requiring a large enough battery to supply this power without drop in output voltage. You may want to consider a 12V system instead, reducing the current requirements.
If you power from 12 or 24V supply (wall plug), then you will need to step down the voltage for the Photon and power your valves directly from the 24V supply.
@peekay123 many thanks for your reply,
I may have left out that I’m keen to use either 12V or 24V power supplies. I have Voltage Stepdown Reducers on hand, so therefore could I work with the reduced voltage idea.
Lets say I go with 12V.
That powers my Particle and the Sensor.
Then could i use a wall plug straight to a breadboard to connect the wirings for the solenoids? Im not super keen on buying those from alibaba, there seems to be a large order quantity requried!
Am I on the right track here?
I am assuming this is something similar to a lawn sprinkler, so you should choose 24V AC for your valves since that is the common standard (in the USA). You will be better off getting parts like your valves locally that are readily available.
Each valve is going run $10-15 at Home Depot or Lowes type stores and require around 300-500mA to switch and less to hold. For 5 such devices, I would be looking for a 24VAC transformer that supplies no less than say 5 A. If you ever want to expand your system, I would get a bigger transformer now.
I would use relays to switch the power to the valves since they are AC. You still need transistors and diodes etc. to drive the relays but smaller ones will do.
I would power the Photon from a separate supply if possible since the switching noise on the 24VAC could be a problem for you. If you have relays controlling the valves, each side is completely isolated, which implies fewer electrical problems over years of operation.