I'm new to the world of Arduino and I'm going to be wiring some electric solenoid valves to a relay shield and I'm just wondering if I can use the relay as the power supply or if the solenoids will need their own power supplies. I think they only draw about 0.5amps each, but I'm not certain. Below are links to the items I plan to use.
Thanks in advance!!
IMO you could use that relay card to control those solonoid valves.
You should install kickback diodes across the solonoids.
The relay card and solonoid valves must be powered by external power supplies.
Keep your wiring neat and short as possible.
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So I would wire kickback diodes between the solenoids and the relay to avoid power going back in to the relay?
Thanks for the advice! I just found out about the world of Arduino. Exciting stuff.
So I would wire kickback diodes between the solenoids and the relay to avoid power going back in to the relay?
No you wire it across the solenoid that is in parallel with it. Connect the anode to the -ve end and the cathode to the +ve end. This is called being reverse biased so that normally no current flows through the diode at all.
I'm just wondering if I can use the relay as the power supply
The relay itself can provide no power, a relay is just a contact closure.
I think they only draw about 0.5amps each,
There is nothing 'only' about half an amp.