I have a PCB with both mains and low voltage.
The ground plane of the low voltage side is kept distant from mains (separation marked with a white silkscreen line), and separated with cutouts.
I am wondering why a main's protective earth line without solder mask, close to the separation (see image), is never made in that kind of circuit?
In my understanding, any high voltage buildup or contamination will first jump to earth before reaching the low voltage side
Does that argument change if the low voltage GND is connected to the mains voltage earth (say through the low voltage PSU)?