Assembling my project involving solenoids

Hey everyone,

I'd really appreciate a nod or point in the right direction with the assembling of my project. It involves 4 solenoid valves controlled by my Arduino Uno.

I'm going to wire the solenoids via a plug for the wall, in series. I'll be using transistors to control the solenoids on and off. The Arduino will be powered separately by an adapter. To complete the picture, the valves are 220/240V and 6.6va. I'm from the UK.

Thanks for reading,

Mikey C

I'm going to wire the solenoids via a plug for the wall, in series. I'll be using transistors to control the solenoids on and off.

I have no idea what this means, but do you have insurance?


Sorry, looking at my post, its not quite clear. I meant have them wired in series, and attached to a plug so I can use the wall socket.

And yes, I'm insured :-)

So, you have four solenoids wired in series across 220 volts?

How are they wired to the Arduino?

Yes. Although reading that, they maybe should be parallel as I wand to wire them and control them through transistors.

Thanks for reading and helping, thus will be my first decent Arduino project.

Reading this, it could be your last.

Oh dear.

What am I doing wrong?

Who knows? Let's have a schematic.

Recently I used a solenoid valve in a project where I controlled this by a small pnp transistor and a solid state relay. Just to get a safe separation between the Arduino and the 230 VAC.

I can send you a schematic, if you want. Don't know how to insert a jpg in this post... :-/

BR, Dries

You may want to get a kit like below to save time. They can work from the digital pins of the arduino.

You can switch the solenoid with the relay.

Thanks everybody for your time.

Heres a schematic

AC mains, through a transistor? No relay?

Funeral plan in order?

Can you post your address so we know where to send the emergency services when we don't hear from you?


So before my other half gets her hands on my life insurance, what can do to make this project safe?

Mikey C

i'd go for relays, I think

I thought relays were pretty much the same transistors. What type of relays do I need, and where would I place them in the circuit?

They are similar, in that they are both a form of switch, but relays don't explode when you put mains voltages across them. Look for low voltage coil and mains-rated contacts.

Do you mean something along the lines of this?

I'm sorry for sounding a real idiot. I've been reading loads on electronics, and related info. But I learn by doing, looks like I'm lucky I've been able to turn to you guys for advice before hurting myself.


Mikey C

Something like this should work fine:

Do I replace the transistors with the relays? Or do I put them in the circuit like D. Neleman's reply and pdf?