Arduino, relay shield and 12 solenoid valves wiring

Other Hardware General Electronics
1

Hi all! I'm new to electric and electronic, and I have a very big doubt on a project i'm working on..
I'm building a machine with 12 aspiration channels, working one at a time. For this purpose, I've bought 12 solenoid valves VT 317 (ideal for vacuum, 24V DC, 6W of consumption), and a Relay shield to control them with an Arduino Mega.
I've tested the circuit with only one valve, and everything works fine (open for 1 sec, wait 1 sec, close for 1 sec, etc).

My problem is: How can i wire 12 of them together? Can I connect all the - and + wires together? What tool do I need?

I've attached a photo of the circuit.

Thank you!

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2

That relay board is for 24V, you cannot power it from a 5V Arduino, you could power the board from your 24V supply and possibly control it with Arduino, however you CANNOT put 24V on an Arduino I/O pin. Need to see a datasheet for that relay board before I can advise any further.

3

Hi,
Why not use one mosfet that can handle all 12 solenoid? Or use 3 mosfet to handle 4 solenoid each.

4

Or use a TPIC6A595 that can drive 8 solenoids directly. No relays needed.

Two (or more) of those chips can switch 16 (or more) solenoids, and only use 3 Arduino pins.
Leo..