Mentioning it just because I didn't see it addressed in the article: AC compressors & fans can be a significant current draw. If you want to replicate this project, it's probably worth checking the amperage ratings for whatever smart plug you use. Something intended to switch lights or a room fan may not be up for the task of repeatedly starting a compressor. Even if the AC unit only draws 15 amps (an so is fine to plug into a wall), inrush current could be an issue for an traic or SSR-based smart plug.
Yes, indeed. If it's a cheap one, it's starting current will probably be 4x it's run current. But it's probably a 400 watt unit, and at 1600 watts for starting, barely within spec for the tiny relay in the smart plug. That said, I have blown the relay in one of my smart plugs with switching motors. But I cycle a dehumidifier in a similar way, and that's been running for two years now.
RIB relays[0] are inexpensive and can handle higher loads than smart plugs, if you’re looking for something that can handle higher loads. Above 30A, a contactor or starter would be more appropriate.
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Mentioning it just because I didn't see it addressed in the article: AC compressors & fans can be a significant current draw. If you want to replicate this project, it's probably worth checking the amperage ratings for whatever smart plug you use. Something intended to switch lights or a room fan may not be up for the task of repeatedly starting a compressor. Even if the AC unit only draws 15 amps (an so is fine to plug into a wall), inrush current could be an issue for an traic or SSR-based smart plug.
Yes, indeed. If it's a cheap one, it's starting current will probably be 4x it's run current. But it's probably a 400 watt unit, and at 1600 watts for starting, barely within spec for the tiny relay in the smart plug. That said, I have blown the relay in one of my smart plugs with switching motors. But I cycle a dehumidifier in a similar way, and that's been running for two years now.
RIB relays[0] are inexpensive and can handle higher loads than smart plugs, if you’re looking for something that can handle higher loads. Above 30A, a contactor or starter would be more appropriate.
[0] 20A relay https://www.functionaldevices.com/support/downloads/datashee...