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I'm sort of an electrical engineer. Increasingly things don't run directly off 120/240V directly. Anything with a power supply could be designed to run of 48V DC nominal. My slight obsession is that really the world needs a low voltage standard. Things like lighting, low power appliances don't need 120/240V.


I'm with you, and actually bullish on this to be a viable way forward.

48V DC has been eyed already for a potential standard to emerge. Doesn't need massive cables to deliver decent power (4A ~200W). There is enough hardware around coming from use cases like EV and Boats that could make it work. Many battery solutions already 'talk' 48v without lossy stepdown of voltage, etc.

Big plus is that the regulation is A LOT less strict for <48v DC compared to AC 110/220/240.


I worked as an electrical civil engineer for few years.

>> the world needs a low voltage standard we have high voltage standard because it means we can have low amperage to transit same VA.

Because voltage doesn't kill, amperage does. It's for safety.

DC is far more safer then AC, but it's not that much safer. If we convert 20A 240V AC (very bad, you can't move your hands away) to 48V DC we get a wooping 110A (instant death)

But if we convert 20A 120V AC, we'd get 55A 48V DC. It's on the same level and has the same problem with moving your hands away.

My country used 220V (as most do!) so switching to DC would mean huge safety threat, but for 120V countries I'd say – go for it!


Not an electrical engineer, but doesn’t the voltage combined with the bodies resistance dictate the amperage? So anything under 50VDC just can’t transmit enough amps through the body to be harmful?


This is correct.


I'm slightly afraid of a world where USB-C PD is going to be that standard.


Perish the thought.

You plugged your class EVTF television into a class ETVF receptacle and your TV caught fire? Shame shame on you.




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