hey community,
as the subject says, i have some questions about the 4Relay shield.
I have to switch on/off a magnetic valve for compressed air (approximatly 3bar). The valve has the option of 12V DC or 24V Dc with a 1W coil.
is the Relay shiled useable for this? (I think yes, but it's better to ask)
And what kind of power supply would you suggest?
kind regards,
Wosche
You need to post a link to the datasheet for the Relay Shield.
Relays usually have their voltage and current limits printed on them.
...R
Of course. It is the general 4 relay shield of the arduino store for example 4 relay shield.
I know i only need one relay, but i haven't found something that suits more.
Also i would need a power supply. what kind of would you suggest? especially for this low power valve?
Unfortunately that link does not list the current and voltage rating of the relays. I suspect it would be quite satisfactory but I can't be certain.
Relay boards like this one are widely avaliable with different numbers of relays. They are cheaper, but not as convenient as a shield.
...R
Allright I have seen these too. And they should suit this project.
What kind of power supply would you suggest? I wanted to take a simple plug in power supply and rip up the two wires but I couldnt find anything with a current that low.
It does not matter if a power supply can provide too much current - the device will just take what it requires. The important thing is to choose the correct voltage.
...R
Summa sumarum ... Just to clearify. 12VDC/0->1Aplug in power supply to the relay and gnd to the coil of the valve. Controlled with a 5V digital output of the Arduino.
Schematic attached.
Should i use a diode attached to the coil?
Kind regards and thanks for the help
Wosche
That looks OK. A diode across the relay contacts (to dissipate the energy in the coil when the relay opens) would be a good idea. Arrange the diode so it does not normally conduct the battery power.
...R
