Wallpapers from The Verge | 19mm Momentary Push Button

I have been hit HARD by one leg of 440v, 3 Phase power running the 2.5 HP motor of industrial manufacturing equipment. I was on a cement floor, and wearing combat boots at the time. I am sure that helped, but my right arm and shoulder hurt with a strong, but dull ache for over a week afterwards.

I don’t know who all of you people are, but stop being ridiculous. This guy made an ESP8266-based TRIAC switch, and gave the design away for free. He has ample warnings on his web page about this project. I encourage anyone who wants to use this design to research the subject thoroughly to make sure they understand what they’re doing.

Australia is similar, except 3ph is uncommon in a house. There’s 3 phase at the kerb and each house is connected to one phase.

But despite them being ‘commercial’, they’re still pretty hideous bits of cheap Chinese kit that I wouldn’t trust as far as I could throw them.

The number on this photo is a little misleading. 337 mpg! I think I shot it after having the car for about ten minutes, nearly all of it without using the petrol engine. Still, it’s a nice little tease for any friends riding along.

Before I bring the tools out, I’m going to ask you questions to get an idea of what’s going on and where to look. You might have your theories about what’s wrong and what my questions mean, but don’t give roundabout replies to match those assumptions. Giving me straight answers will save us both time.

Note: Not all certifying agents offer online lookup, and some have a lag time for posting new certificates. If you are unable to find a certificate online, contact the certification agency or supplier for further verification.

You don’t need a big contactor to switch 1A at 120v, you can get little “ice cube” relays that switch up to 10A at 120V and they have a plug-in base so easy to change out when they inevitably fail. Most of them, in new perfect condition, make barely any sound. Nothing compared to the noise of fans and stepper motors. The only issue I can see is running AC mains voltage through wiring that is going in parallel with low voltage. Would need to use thick jacketed, shielded cable to prevent too much EMI. Maybe it’d be better suited using a separate transformer just for the heated bed, rectified/regulated but still a higher voltage for better efficiency. Speaking just from my experience as an electrician and hobbyist level electronics/3d printing experience.

>Basically, cheat until caught. I’m a high schooler in America, and my “fellow peers” pull the same bullshit- and then when they get caught, they get mad at the teachers. >And their government seems to actively turn a blind eye to all manner of this nonsense. Aaand so do peers at my school.

The best defense is to make sure you buy from reputable sources, not from some backyard hardware store or eBay.

So a 20 amp breaker is designed to take the load shift on startup. A 15 amp breaker will carry the nominal load, but that surge on startup will kick it every time. In the days before switching supplies the input voltage would vary from 108 to 115VAC where I did work. This occasionally caused breaker trips on the unprepared circuit. I learned to spec high enough to minimize that issue and keep a safety factor in play.

The earth ground connection won’t prevent you from being shocked unless it’s a GFI outlet. The soil resistivity in most places in the US doesn’t cause enough current to flow to earth ground to trip a normal breaker. Bonded ground systems are better, but if the bond from neutral to earth ground is far away from the short it might still not trip a normal breaker.