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points by speleding 2 days ago | 0 comments

I read an article about a house that was converted to use DC instead of AC as a trial. The most surprising part to me was that most household appliances simply kept working because they already contain a AC/DC rectifier anyway which works fine if you connect it to DC.

[–] bluGill 2 days ago

That depends. Anything with a transformer will not work on DC. Some power supplies don't have a transformer directly connected to mains and they will just work. A large number of appliances use universal motors (anything in your kitchen) and so they will just work. Heaters are typically just resistance and again will just work.

However there are a lot of things that won't work on DC as well. Since very few people are running mains voltage DC labels often will not tell you if it will work. (I've toured ships with mains voltage DC and those outlets are labeled - I assume the crew is trained - or perhaps was since this is just a museum now and I'm not sure if current ships use DC)

[–] treis 2 days ago

"just work" depends on the DC voltage, right? A heater works just fine on 120V DC but less well on 48 and probably pointless on 5.

[–] solyin 2 days ago

I get what you're saying, but there are some hand warmers that just charge off of USB 5V.

[–] treis 2 days ago

Right it works if it's designed for it. But hooking up a 5V source to a stove element isn't going to cause much heat.

[–] bluGill 2 days ago

V=IR applies. I've seen 900 watt heaters running on just 3 volts. You need big wires and low resistance to pull it off but it works

[–] treis 1 day ago

Right it works if it's designed for it. But hooking up a 5V source to a stove element isn't going to cause much heat

[–] dalyons 2 days ago

wait what. rectifiers will just seamlessly work on DC? TIL thats wild