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by bluGill10 hours ago |
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upvoteby marcosdumay10 minutes ago|
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> because transformers are relatively cheap, low maintenance, and efficient

And because that problem of galvanic corrosion the GGP talked about, and the mirror one of material aggregation don't happen. And it also makes switches more reliable.

Both are less dangerous on telephone lines. But are very important on electricity ones.

1 - It won't break your posts, but can easily short small contacts.

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upvoteby jcalvinowens9 hours ago|
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> When the system is AC ground makes no difference.

With AC it's about where the ground is attached along the length of the transformer secondary. In the EU they ground one of the ends of the secondary, in the US we ground the center point.

I don't get to say this very often ... but the US way is objectively safer with no downside: 99% of human shocks are via ground, and it halves the voltage to ground (120V vs 240V). A neutral isn't required if there aren't 120V loads.

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upvoteby Liftyee5 hours ago|
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I agree that the US voltage is safer (with the tradeoff of lower output powers available at your outlets). However, I suspect this is more than negated by the US plug design, which carries a much larger risk of shocks than almost all EU plug designs (Schuko, British/Type G, etc...)

- uninsulated metal pins make contact with supply while partially exposed - much smaller distance between metal pins and the edge of the plug

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upvoteby jcalvinowens5 hours ago|
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100% agree the US plug designs are terrible.

But there's no inherent power tradeoff: you can have 240V outlets in the US, with the two prongs both 120V to ground. They're just really uncommon in residences.

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upvoteby bluGill2 hours ago|
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Dryers and Stoves/range outlets are very common in US houses. Of course they are generally hidden behind the device and so most people are not sure if they have them at not. They are also reasonably common in garages (welders, air compressors, table saws... - if your hobby needs them you install them, otherwise you won't have them).
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upvoteby crote3 hours ago|
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In the EU it is quite common for houses to have three-phase power. If you squint a bit, the grounded neutral of the Y transformer isn't entirely unlike the grounded center tap in the US. The voltage is a lot higher, of course!
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upvoteby Dylan168071 hours ago|
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> If you squint a bit, the grounded neutral of the Y transformer isn't entirely unlike the grounded center tap in the US.

Yes, but you only get the safety benefit on three phase equipment.

In the US there aren't a lot of 240V plugs, but if you get some installed you can get the safety benefits with plain old consumer goods.

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