Positive earth understanding

[broncoupe]

This is really embarassing i cant get my head round Positive earth
So have a classic with spotlights that are relay switched at the the loom i have -12 volts so would it be as simple as grounding the other wire after it passes through the bulb
So is it -12volts like a negative potential of 12 volts which when going to the chassis +12volts becomes the complete curcuit
I know im not explaining it correctly but need to get my head around it

 

[UNG]

Positive Earth means the battery positive is connected to the vehicle body and all the wiring is connected to the negative battery terminal
So all equipment on the vehicle is supplied with +12v from the body and the switching is on the negative part of the circuit

 

[littlespark]

Typical.

I type a dozen or so lines and somebody gets there before me.

As far as + and - go…. The only issue would be if you connected something with a diode… such as LED lights… but as it’s a classic… it won’t have them.

Modern radios might also be an issue where you need a permanent 12v+ and a switched 12v+ through ignition