I am looking to give a relay board an independant power supply to protect the arduino uno board.
i have a 5v regulated transformer.
I know i remove the jumper cap and attach 5v supply to the JDVcc pin.
It then looks like I need to attach the ground to the ground pin.
However the transformer has positive neutral and earth outlet terminals.
Postive is the 5v supply but which is the ground the neutral or the earth.
Apologies if this is basic stuff but bear with me.