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The real reason why North America uses 120v instead of 240v.
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Someone:

--- Quote from: IanB on November 25, 2022, 12:39:24 am ---
--- Quote from: Monkeh on November 25, 2022, 12:29:33 am ---The push-fit Wagos and similar are effectively identical to lever operated types, just without the lever. They're of far higher standard than the crap in receptacles, thankfully - there are meaningful standards applied to them.
--- End quote ---
There is an amusing tier system of receptacles (plug sockets) here in the USA:

"Consumer grade" -- Quite likely to melt and catch fire
"Commercial grade" -- Probably will not catch fire
"Hospital grade" -- Very solidly built, likely to last

There is a corresponding price scale, which means few people are going to spend the money on hospital grade items.

Guess what gets installed in new homes?

(Also, guess why the latest electrical code insists on arc fault circuit interrupters?)
--- End quote ---
This is the downside of 110V delivery, increased risk of fire from the electrical installation. Such fires are barely evident in 240V systems historically, but widespread multi kW vehicle charging will likely change that!
IanB:

--- Quote from: Someone on November 25, 2022, 02:01:30 am ---This is the downside of 110V delivery, increased risk of fire from the electrical installation. Such fires are barely evident in 240V systems historically, but widespread multi kW vehicle charging will likely change that!

--- End quote ---

It's more a question of quality control. For instance, I have a 1500 W electric kettle, which has a figure 8 zip cord and moulded on plug. When I use the kettle, the plug gets notably warm, even hot, where the cable joins it. I'm not sure what kind of connection exists between the conductors and the plug pins hidden inside the plastic moulding, but I don't think it is very good. Soldered? Crimped? I have my doubts.
Siwastaja:
North America does not use "120V instead of 240V". North America uses BOTH 120V and 240V. It's a pretty clever system although one could claim ours is simpler, with one voltage and one plug. OTOH, our plug is limited to ~2.5kW continuous. Households in the US of A have higher-power sockets available, if not in every room, but at least a few in the house!
jonpaul:

My recollection...

Thomas Edison setup first electrical distribution in 1880s Pearl St DC generators serving lower Manhattan.
The gutta percha insulation led to 100V tension.

Later, the industry advanced to AC distribution, the service voltage was increased to 120V to compensate for copper losses.

Nowadays Con Edison has a 12 kV mesh underground network, with 12 k to 240V/ 120 single phase or 208 V delta three phase.

Just the ramblings of an old retired EE

Jon
snarkysparky:
My guess is that the vast majority of electrical shock fatalities are in industrial settings.  480 VAC and much higher.

So unless there is data that breaks our household electrical shock fatalities the data is meaningless to the discussion.

Also i would guess there is some nonlinear effect in the current induced by the voltage.   48 VAC is unlikely to provide more than a tingle unless wet.  120 VAC could be just an annoyance.  Many electricians in the USA test for hot on 120 VAC by lightly touching the wires.  Step up to 480 VAC ( which is 277 to ground)  and things become much more serious.

In Britain what is the voltage to earth in their systems?
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