Hello,
I'm attempting to create a water shut off system with my Rpi 3. I purchased 2 24V AC 3/4" Normally Closed Solenoid Valves and I'm trying to activate them with a relay. Any suggestions as to what type of relay I should use? I've been looking for one but I can't seem to find one that works. The power supply is a standard American wall outlet.
Thanks,
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gannonziviello
- Posts: 1
- Joined: Tue Mar 24, 2020 9:20 pm
Re: Controlling 24V AC Solenoid Valve by solid state relay
CAUTION! SAFETY FIRST!
as AC 220V mains will be involved, this project is best done with a supervision of a certified/licenced electrical technician
on wrong move, may cause injury to your or anyone near you, and/or may cause damage to property.
first you need to get a step down transformer to convert AC 220v to AC 24v
the rating will depend on the total power required by the solenoids,
plus safety factor of at least, say, 50%, better if at least twice the total,
and get the nearest one (higher rating) available.
to select the relay, again check the ampere rating of the solenoid valve, and get a relay with a rating of at least twice the ampere rating.
once the relay is selected (it may be some of those pre-built modules for the arduino ecosystem),
then you'll need to make an additional circuit to be able to activate that using the RPi's GPIO.
there are lots of examples of that circuit here in the forum, with schematics masterfully made by @pcmanbob
SAFETY FIRST!
as AC 220V mains will be involved, this project is best done with a supervision of a certified/licenced electrical technician
on wrong move, may cause injury to your or anyone near you, and/or may cause damage to property.
first you need to get a step down transformer to convert AC 220v to AC 24v
the rating will depend on the total power required by the solenoids,
plus safety factor of at least, say, 50%, better if at least twice the total,
and get the nearest one (higher rating) available.
to select the relay, again check the ampere rating of the solenoid valve, and get a relay with a rating of at least twice the ampere rating.
once the relay is selected (it may be some of those pre-built modules for the arduino ecosystem),
then you'll need to make an additional circuit to be able to activate that using the RPi's GPIO.
there are lots of examples of that circuit here in the forum, with schematics masterfully made by @pcmanbob
SAFETY FIRST!
"Don't come to me with 'issues' for I don't know how to deal with those
Come to me with 'problems' and I'll help you find solutions"
Some people be like:
"Help me! Am drowning! But dont you dare touch me nor come near me!"
Come to me with 'problems' and I'll help you find solutions"
Some people be like:
"Help me! Am drowning! But dont you dare touch me nor come near me!"
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davidcoton
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- Contact: Website
Re: Controlling 24V AC Solenoid Valve by solid state relay
[pedant]LTolledo wrote: ↑Wed Mar 25, 2020 9:12 amCAUTION! SAFETY FIRST!
as AC 220V mains will be involved, this project is best done with a supervision of a certified/licenced electrical technician
on wrong move, may cause injury to your or anyone near you, and/or may cause damage to property.
SAFETY FIRST!
The USA mains is 110V, not 220V.
Still potentially lethal, so the suggestions are still appropriate.
[/pedant]
Also, be aware that not all solid state relays will handle AC.
Signature retired
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Burngate
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- Contact: Website
Re: Controlling 24V AC Solenoid Valve by solid state relay
Should we interpret that as a "wall-wart", plugged into a socket and producing 24V AC on the end of a pair of wires?gannonziviello wrote: ↑Tue Mar 24, 2020 9:24 pm... The power supply is a standard American wall outlet.
If so, as long as it can supply enough current for the two valves, safety should already have been taken care of.