Comment on USB-PD is a de-facto low-power DC voltage standard, with USB-C being the universal plug. Hurray!
cmnybo@discuss.tchncs.de 9 months agoSolar panels use MC4 connectors. They are weatherproof, they lock together and they fit the thick, weatherproof cables used for solar power. They can handle fairly high voltage, but they can not be connected or disconnected under load though.
The Anderson Powerpole connectors are a good choice for DC power. I use Anderson PP30 connectors for most of my 13.8V stuff. They are robust and fairly small.
Most electronic devices will just rectify AC into DC before stepping it down with a switch mode power supply since that’s smaller, lighter, and cheaper than using a mains frequency transformer. It’s pretty rare to find a mains frequency transformer in consumer electronic equipment today.
solrize@lemmy.world 9 months ago
Yeah probably true about 60 hz transformers, even for higher powered devices like desktop PC’s. They still have pretty big internal inductors though.
For permanent installations like most solar setups, I don’t think uniformity of connectors is that important, as long as it’s non-proprietary and you can order it from a catalog.
For phones and laptops, wireless charging is probably the way forward. More than additional standardized chargers, I want standardized and swappable batteries, for phones, laptops, power tools, etc. The chargers will follow.
Trainguyrom@reddthat.com 9 months ago
Wireless charging is super lossy though and generally far slower than charging over USB. I’m sure some of that can be overcome with more research but I have a hard time believing wireless anything will ever be as efficient as wired
solrize@lemmy.world 9 months ago
Phones or laptops should probably accomodate wired charging (though count on Apple to eliminate it anyway), but most of the time, wireless could be the norm. Convenient, avoids wear on connectors, etc. I think there are some Samsung phones with two-way wireless charging, so you can stack one phone on top of the other and transfer charge. That seemed crazy to me given the non-removable batteries but whatever.
That reminds me of another USB PD idiocy that I forgot to mention earlier. There are many devices like power banks and even some phones, that can both send and receive charging current. E.g. you’d charge your power bank from a wall cube, and later use the power bank to charge your phone. In the pre-USB-C era, power banks had separate connectors for input and output. Now the two functions share a single connector and the cable is the same at both ends.
So if you plug one power bank into another, how does the setup know which one is the “charger” and which is the “chargee”? THe spec says they are suppsed to choose at random! I guess you are supposed to look at the activity lights and if the current is going the wrong way, unplug and replug the devices until they go the way you want. This can lead to a situation where you plug your phone into a power bank, but the phone ends up charging the power bank instead of the other way around.
I imagine you can prevent or at least stop this somehow if you are attentive enough, but it still seems like crackhead engineering to me.