URGENT: School project - arduino uno humidifier pls help 😭

it was mentioned before 5V / 300mA

the USB C is just so that you can power the thing directly with a phone charger. you use the button to turn it on or off.

Me, too. But... i don't see a solder blob. Maybe on the reverse side?

To power it at 5V.

Some have even pads on reverse side for this purpose.

something to read here

➜ basically you just short the button and it's ignored, the module will be always on when you power (and may be after 4h the timer kicks in but since the button is pressed, it will likely start again)

So, there is no need of 12V. External 5V supply with sufficient current capacity is to be passed to the Module (across the indicated + and - of post #45) via a relay under UNO's control.

From where you got that 12V in the first place?

I assumed as OP was saying about connecting a relay. Now, I know that the Mist Module works on 5V/300mA and the relay is needed to control the On/Off states of the Module by UNO.

The mist module works when I press the button

Uhh the mist module in your image doesn’t quite match mine..

Show the other side...
These pads might be the button pads... to "short" or use for the relay.


Can you measure continuity between the pads I circled (1) with button released (2) with button pressed. It should read (1) open and (2) closed. If so, this is where you can wire the N.O. and COM contacts of the relay.

So he didn't prepare the board for you with blue and black wires soldered on?

That's the translation of the markings

I'd be tempted to say that the 2 pads are indeed to short the switch.

he didnt solder it he just inserted in the like little circle with + and - then with male to male wires to the breadboard

that's calling for troubles... you are not really sure the contacts will be strong enough for the power to be stable... really it should be soldered.

Then you need someone to solder the cables and the jumper pads.

Okay, I'll ask my teacher if he can solder it for me since thats really the way for it to work properly. thank u

I think shorting the pads in Post #55 would make the module "always on".
I think the relay needs to be placed here for the Arduino to control the make/break.