Hi all and the mighty @LarryD especially.
So I got my components today and tried building a test circuit on a breadboard. I've put a picture of it here, probably worthless but maybe you could understand something from it.
My idea for this circuit was to put a resistor instead of the motor and test the voltage drop across it with a multimeter.
I just wanted to use "one side" of the circuit; one relay which will be NC short, and it's NO will be connected to power, and at command by Arduino Uno's pin D7 it will close the circuit and there will be voltage on the resistor. The other end ("2nd side") of the resistor is simply connected to ground.
Long story short there was 0V across the resistor and although it's leds still work, I can't upload anything the Arduino now...
Maybe you can identify my mistake, I think maybe I got something wrong with the relay's pins.
I also added it's datasheet(model G5SB by Omron), maybe I haven't interpreted it correctly. I connected pin 3 (on the datasheet) to the power supply and pin 2 to the resistor.
I've also put here a schematic of the circuit.
Thanks in advance
