Hi,
I have 2 electric wall heaters, dumb except for a 1-12 dial.
So right now to add a thermostat to them I used the bt temp sensor in each room and and Tuya Smart Switch (16A) on the outlet connection, because on the mains they are both connected to 1 20A breaker (so I need to add the switch in the rooms otherwise I can’t control them separately)
While the system works, and I think 16A is enough, I want something more safe than those tuya switches, the problem is that they also need to fit the outlet, any suggestions?
BTW, if you’re not aware, your “switch” is basically a relay - you’ll probably get more results if you search for a “20a wifi relay” vs a switch. Also, I should likely add (since this cost me $1000 by making the mistake) that there are two types of relays - wet and dry. A “wet” relay will put whatever power you put in to it out to the connection it closes when it turns on. A “dry” relay takes in power to run the relay, but closes a separate circuit when it turns on, and will not put any power on that circuit unless you explicitly wire it up to do so. From the sounds of it, you’ll want a “wet” relay that takes in 240v and puts out 240v.
I don’t necessary want a wet relay, but I think I need one, since I only have the mains cable (Line / Neutral) connected directly to the heater (I put the 16A relay on the connection).
Yes, I agree it’s a better choice than the random devices from AliExpress. Still I think OP wanted 20A.
Shelly (at least some models, not sure about 1 plus) has the option to limit max per (meaning it turns off when the limit is reached), but I’m guessing it can’t really be relied on as a safety feature.
Find one 20A that’s tiny.
16A relay might fail before 20A breaker strips but so will any device (for example the 6.5A heater), so I don’t see security problem here. (The code can disagree this though)
I am definitely no electrician, but if your load line is on a 20a breaker, that means the wire should also be rated to carry 20a - but it could carry more, slowly, without tripping the breaker. When a device is rated to a certain amperage, it means it should be able to safely carry that, plus a bit more without failing (catching fire/melting). The breaker should trip before any damage happens to anything connected to it.
I personally wouldn’t risk it if you can find a 20a rated relay as well - the difference being that if something were to happen, you’d be at fault with a 16a rated relay, vs a properly rated one would then shift the blame on to the device (if properly installed ofc).