I'm helping my brother find a way to turn a 240 volt device on and off through the use of his smartphone, home automation devices, or computer. If it matters the intended device in question is an air conditioner but if we all want to keep this amateur radio related then pretend the device is a legal limit amplifier or heavy duty battery charger. For some background I'll explain further. My brother has a detached garage that was intended to be a workshop of sorts before he had a wife and kids. Since then it's turned into a playhouse. Since it was intended as a workshop it's got plenty of outlets along one wall for where a work bench would have been, a 30 amp 240 volt outlet intended for a welder in one corner, and in another corner a 20 amp 240 volt outlet intended for a large table saw. The shed is insulated well and so he's been able to keep it warm on all but the coldest days with a couple 240 volt heaters, a smaller one on the "table saw" circuit and a larger on the "welder" circuit. Through the summer he's able to keep it cool and dry enough for comfort on most days with a standard 15 amp 120 volt air conditioner. After a shockingly large electric bill one month from leaving something on he bought some Belkin Wemo remote control outlets (the same as or similar to this one: https://www.belkin.com/us/p/P-F7C027/ ) so he can check if he left something on from an app on his phone and he can voice control them with one of those Google home automation devices. He still has to check on the 240 volt heaters manually but at least he can control the 120 volt air conditioner and some cheap 120 volt heaters. He'd like to be able to get a larger air conditioner because what he has can't keep up, and what he's got is already the max size he could get on 120 volt. The 240 volt heaters he'd like to control as well, as the smaller heaters can't keep up on colder days, and he's paranoid about leaving them running while he's not there. I already ruled out some options. He doesn't want to run any new wires. It's a garage with surface mounted conduit for wiring so we can get at most everything but no one wants to try to take that apart, run new wires, and put it back together. He's willing to do some pretty minor alterations if he must but there is a line based on funds and approval from the "boss". Also ruled out are many "hacks" I offered to construct to control the 240 volt circuit from a 120 volt Wemo swtitch. The "boss" doesn't want her children playing around something that's some kind of high school science project. I can understand as it appears she's seen some of my previous "works of art". What I'd like to find, but have been unable to locate just yet, is a Google Home compatible 240 volt switch. It doesn't have to be Google Home but it does have to be automated by a popular home automation system. My brother has played with home automation from Google, Amazon, and Apple, and so he can switch to whatever works. Failing that I'm thinking of using similar devices to that Wemo intended for use outside the USA. In many nations the standard voltage is 240 volt and there are off the shelf adapters for making them work on USA standard plugs. This should make it pass inspections. To make things neater and safer it might be nice to find a foreign outlet that fits in a standard USA electrical box, or can be somehow connected safely to USA standard conduit. I believe I found things like this once but I didn't make proper note of it and lost where I found them, but I can probably find them again. I'm thinking that there's enough readers here that have tried similar projects that someone might have some good advice. I'm not really into trying to do this home automation stuff but I'm beginning to see this as more than a novelty. If I can get this to work for him then I have some similar things I'd consider for myself.