Hello eveyone!
I have some issues with using a relay.
I tried to connect my relay 2 different ways, but non of them worked(I'll add the connections).
When I connected the Relays VCC to Arduino 5V at least the led was working, but on the NO side the 12V didnt show up. Any ideas?
Some infos: Arduino UNO, 12V DC Battery, SRD-12VDC-SL-C Relay
Thanks for the answers!
how is the Arduino powered ? the GND on the arduino side of the relay module should be the Arduino GND. Often the really will be powered not by the Arduino itself (although 1 relay could be OK).
there are tutorials out there, here is a random one
Why did you post this topic in one one the Covid19 categories of the forum ?
It has been moved
It was an accident, sorry!
Once I used only the USB connection, but I tried to connect a powersupply to the Arduino, basically nothing changed (It was a 12V PS).
Thanks for the tutorial I'm about to take a look at it.
P.S.
Forget the second schematic ( use it only if relay is 12V, then connect also the negative of the battery to the gnd of the relay module and the gnd of the arduino )
No. There is no wire that should come from the battery to the Arduino side of the relay
the command side should have GND from the Arduino and a wire to the command pin. The 5V in on the command side could come from the 5V pin on the arduino (probably OK if you have only one relay)
Can you clarify how you plan to power the arduino? Is that from the same battery?
I am about to attach a link from my project how it "works". You could see what is working and in which funciton is the problem. I checked several times on the NO side of the relay there is 0V all of the time
https://drive.google.com/drive/folders/1AQ8mxGM-V9shMgwfUK1kO-rfWipSsQl9?usp=drive_link
No I won't power the arduino from the same battery, I have a Router adapter (12V 1A DC) and that will power the Arduino
so one side is "the arduino side" and the other side is "the battery / load" side. No wires from one side should go to the other side.
I don't click links. Post stuff here directly in the forum.
Ohh ok.
I can't send it here so... 
what do you mean ?
you can post code, you can post pictures.
Closed
Could my battery (NOT the Arduino side) cause the problem that it has some sort of problems what I can't detect?
Your initial drawing had only one relay and now I see two...
can you clarify where all the wires I see go ?
below the bottom module here
there is a yellow jumper label JDVCC. Do you understand what this is for?
How do you say is a 5V relay????
Is last line saying srd-12vdc????
good point - eagle eyes !
So just to clear things up: Its a project of a door locking system and there are 2 doors.
The top module is also connected just like the bottom one. The COM (the middle gate) gets the 12V DC from the Battery and the NO gate goes to the door lock.
Im not 100% sure about that. I read something about it but I don't get it...
