Help with solenoid valves

Projects General Guidance
1

Hello everyone,

I bought the basic 1/2" plastic 12v solenoid valve from adafruit.. Today I used it and it has a very very slow flow rate.. Have I connected it wrong or does it literally drip out..

I have an 18litre tank connected to another 18litre tank underneath it... maybe I didn't reach the minimum 0.02-0.08mpa pressure...

Any ideas or Is there any cheap and easily obtainable 12v 1/2" solenoid valves without minimum pressures available ?

Thanks,
Elliott.

2

What is the source of the water pressure ? Did you open the valve ?

3

Thanks for the reply.. I don't know exactly what the water pressure is..
I will post a pic of what's going on it might help to understand..

Edit: so there's two tanks.. The top is full of water which when the solenoid activates should fill the bottom tank.. This was a photo before it was wired up by the way everything is now connected

image.jpg
image.jpg2448×3264 1.59 MB

4

maybe I didn't reach the minimum 0.02-0.08mpa pressure...

most of these types of solenoid valves have a minimum inlet pressure for the valve to actually open, the solenoid just operates a latching mechanism and it's the inlet pressure that actually supplies the 'force' to open the value against an internal spring that supplies the force to close the value when you de-energizes the solenoid. The minimum pressure is 3 psi so that equates to close to 7 feet of 'head pressure' to operate the valve. So your choices is to mount the supply tank greater then around 7 feet above the valve inlet or get a valve that doesn't have a minimum inlet operating pressure to open.

5

Thanks for that, I actually understand why now haha.. So would I be able to attach a 12v whale pump which operates 0.6bar of pressure which is 0.06mpa..

If not could you find me a 12v 1/2" solenoid valve with no limits.. I can't find one and it can't come from china as this is a college project that needs to be done by next Wednesday?

Thanks for your help..

6

elliottr:
Thanks for that, I actually understand why now haha.. So would I be able to attach a 12v whale pump which operates 0.6bar of pressure which is 0.06mpa..
Yes, that should work, you just have to turn on and off the pump and solenoid at the same time I guess.

If not could you find me a 12v 1/2" solenoid valve with no limits.. I can't find one and it can't come from china as this is a college project that needs to be done by next Wednesday?
Well that Adafruit site offers a 1/2" brass solenoid valve that requires no minimum inlet pressure requirement, but of course at a higher cost.
Thanks for your help..

7

Lovely job thanks for all your help I appreciate it