I used significantly higher-rated omron relays in a project I did a few years back to switch a 2.5HP motor on/off a few times daily. This area shouldn't be skim

I used significantly higher-rated omron relays in a project I did a few years back to switch a 2.5HP motor on/off a few times daily. This area shouldn't be skimped on; relay contact arcing isn't a joke. This brings me to my second point: I don't see a cycle rating on those relays from the datasheet provided. Most relays are rated for ~1M cycles, some for ~10M or more, but beyond that solid-state relays start to be a thing. And so, I question if people are using mechanical relays to chop 50/60Hz AC power, which from my 30 seconds looking at the article/schematic appear to be what is happening here... That seems crazy to me, and I imagine it requires some exotic contacts in the relays to avoid failure in short order, which these relays don't appear to be. The data sheet mentions they are used for chargers/solar inverters/etc but that doesn't mean they are used at 50/60Hz cycling but likely just as a disconnect/power on function which cycles once per charge/day/etc. Then again, I don't really want to be this guys neighbor since chopping an AC line with that much load is going to generate an insane amount of noise, and I don't see anything in the circuit designed to damp it either.