Xiaomi Mi Mix 3 announced: specs, features, price | Lrd12 Overload Relay

Ok let’s assume you have a coated PCB that that doesn’t promote condensation, now unless you’re immersing your PCB in Argon, the flash over voltage is a function of the air it’s in. Unfortunately this calculation has many variables such as impurities in the air like smog (which cause condensation), altitude (which dictates how much moisture the air can carry), distance between traces (of course) and several others.

Historically, there were two post-war electric utilities, and one contracted with GE for equipment, and the other contracted with Siemens – thus the two wound up with different frequencies.

Remember that, across the same resistance, power goes up with the square of voltage; 120v RMS can deliver 100x the wattage of a 12v supply, and 240v delivers 400x.

Gardner Minshew II threw two touchdown passes and ran for another score and No. 12 Washington State stopped No. 25…

I learned British version of English, but my accent is all over the place. I also speak a bit of Spanish, Portuguese, Latin and a tiny bit of German. I can swear in Russian too, because my wife knows that language. And don’t forget my native tongue, which is Polish.

Because a failure of the sort I have described will not be current limited. You’ll likely start a fire.

I am going to try a rheostat on the input voltage to see if I can drop the rectifier output voltage to around 30v. Right now it works but will pop a15A wall circuit breaker after 15-20 seconds. But it is a super strong magnet. Limiting the current is the key I believe. More later

[It looks like I’m on meds with all my grammar and spelling errors in the post – and I am actually Pain meds and muscle relaxant for a evil frozen shoulder….]

The remote has a few buttons and LED for status. The LED reacts differently depending on the pool’s current mode, so connecting there not only gives you control but also allows you to provide some limited status. It isn’t going to let you monitor pump currents or anything exotic, but it is a simple place to gain access. Using the Arduino pulse input function makes it easy to sense if the LED is on, off, or blinking. Another sensor reads the water temperature. The controller makes it available, but it isn’t simple to read, so the project just reads the raw sensor voltage from the existing thermistor and computes the temperature.

I think the issue is more that 8A might be fine for a light but embedding it where another future operator will reasonably assume it is rated at 15A is not fine.

Of course a safe mains powered heater is possible, but you need a double insulated cable (which is stiffer and heavier) and a reliable strain relief for it. You have to permanently bond the heater PCB to the glass print bed with silicone. You need a fuse and a thermal cut out (thermal fuse) for fire safety, because the available power in the mains circuit is much higher.

Just curious, what size pump do you have? The Sonoff claims 10A per channel, but my 1HP pump needs a 40-50A relay to safely deal with cold-start current. Unless the relays are overspec’d I’d be worried about literally burning out those contacts pretty fast.