Power GeniusXL Remote power

Your example seems expensive and still needs 240 VAC wiring, and locks you into the Sonoff smart switch.

I built my own:

Contractor, with 120VAC coil. :

Installed in this box:

I use these to **** the box:

On the 240 VAC side, I used a 3-foot, 240, 15 amp extension cord, cut in half and wired into the relay, inside the box:

I used a 10-foot length 240 VAC 15-amp extension, of the same as above, to run from my 240 VAC, 15 amp wall plug to the relay box.

I used this cord to run from the relay box to the PG-XL: (other amps may vary)

I cut off the female end of an unused 110VAC cord, and wired to the relay coil. Plug the 110 VAC into your smart switch of choice

I applied this label to the box:

Alan WA9WUD