The Expanse is being turned into an RPG | 220v Contactor Relay

It will only trip the breaker if you have a bonded ground. Soil resistivity has everything to do with it, and is the reason most homes have bonded grounds (the soil resistivity is too high to provide adequate current flow to trip a standard breaker). Unless you have a GFI on that circuit you can still get shocked. Earth ground won’t help you until the voltage gets high enough to cause enough current to flow to trip a standard breaker, and NEC requirements set the limit on earth ground resistivity, the limit they set ends up equaling a voltage of 600 volts required to trip a standard breaker, and that is why most (single family) homes have bonded grounds. Earth ground is only for high voltage transients.

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Just took a few seconds? the speed of light must be a bit slower in whatever dimension you’re living in.

Besides the overexposure bias, I also found the A33′s metering system was prone to more variation than I’m accustomed to seeing in an SLR. The few times I had it locked down on a tripod, shot to shot exposure seemed pretty consistent, but on several occasions shooting handheld, I found significant variation between successive shots, apparently resulting from fairly minor changes in framing. I’d of course expect exposure to vary to follow changes in the scene, but the amount of variation I saw between very similar shots taken with the A33 was unusual.

HVDC interties certainly simplifies some things (stability, voltage control, and frequency syncing & phasing is a non-issue), particularly in lines where their length approaches a quarter wavelength (which makes voltage control at the load end difficult). There are quite a few already: http://en.wikipedia.org/wiki/List_of_HVDC_projects and the list is growing rapidly.

I first thought we were about to see the actual moment when it was about to blow. But this is post mortem autopsy.

Virtually every home in North America is wired with 240V (NOT 220V!) split phase, providing 120V to ordinary receptacles, and 240V (NOT 220V) to larger appliances. Most kitchens are wired with 240V split phase to the (split) receptacles at the countertop, providing a very convenient 240V source if you just wire up the appropriate adapter to take the hots from each phase.

My 2 stage 23 x 24″ CASE snowblower I home-made converted to a 3 hp extension cord electric (240 on the Tesla outlet – peaks at 35 amperes and 7 1/2 hp). I was worried that I had underpowered it but last March when all the gas blowers on the street were stalling on heavy water laden snow, mine just kept barreling down the sidewalk.

After a long, bitter, loud argument with the plant “electrician” I finally got him to check the distribution board, when we opened up the “big grey box” first thing I saw was all the earths, bundled together with tape and just hanging there. From where I was standing I saw a fuel tanker driver hooking the earth lead to his truck, which came into the same box.

Your advice / admonition overlooks the reasonable likelihood that the part wasn’t *really* rated for what it *claimed* to be rated for, nor was it constructed in a manner to keep it safe in the event of an actual failure– as in the article’s example. Such that even if he were a licensed and well-experienced “electrician” (or anything else), it STILL would (could) have failed and caused the same problem. So what you’re saying IS good advice in a general way, but only partially relevant to the actual incident from the article, IMO of course!

I know some policies that clearly state work needs to be performed by “duly licensed” personnel (ie. you better be a licensed electrician or plumber). That’s one of the reasons I did not want to install my own automated transfer switch. Insurance company would possibly deny coverage in event of a mishap.

If you insure that your HV and LV systems are completely separate, and joined only by UL registered galvanically isolating components, only then can you be prepared to say that the logic portion of your system is safe. And doing that maybe won’t make fewer things capable of going wrong, but at least fewer things capable of spectacularly dangerous failure.