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So Where’s My Low Voltage DC Wall Socket?

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Re: So Where’s My Low Voltage DC Wall Socket?

#41

Post by atonse »

rb808 wrote: post #21

I dont think DC wall socket is the problem - its the small electronics that each have their own power pack. Ideally to me every led lamp, settop box, alarm clock, phone, laptop would not come with a power supply box. It would just take a USB cable or similar standard. Then you could buy a good quality power supply adapter that you can reuse for lots of products - and avoid the abundance of random adapters everywhere.

That is sort of happening already. A lot of devices are just using USB standard for their power supplies.

I suspect that with PD, that allows even lamps to negotiate that they need more power, maybe?

Re: So Where’s My Low Voltage DC Wall Socket?

#42

Post by gok »

> USB C meanwhile requires active cables, sockets, and devices, sacrificing any pretence [sic] of simplicity.

Passive USB-C cables should be fine up to 60 watts. Beyond that you need a chip to certify safe construction but that's a good thing.

Re: So Where’s My Low Voltage DC Wall Socket?

#43

Post by rusk »

unilynx wrote: post #38

If none of the current plugs are usable, can we have a low-power plug standard based on PoE? Having both ethernet and low power from one socket would be perfect for IoT devices, save people from having to run Ethernet wiring themselves afterwards, and cut down on wireless spectrum use. And your 'smart fridge' would just plug into both outlets and use a relay to cut 230V if the motor doesn't need to run.

Stop talking sense! Can’t you see there’s money to be made here!

Re: So Where’s My Low Voltage DC Wall Socket?

#45

Post by joecool1029 »

kevin_thibedeau wrote: post #11
Spooky23 wrote: post #5

Earlier quoted context omitted.

The author makes the valid point that USB-A is too low power, and USB-C requires active cables. (Translation: expensive or dangerous)

USB-A can support power delivery. The standard predates USB-C.

In practice I haven't seen USB PD 1.0 in the wild. Most of the non-PD charge standards signal charge rates using varied voltages on the D+/D- lines.

When current manufacturers claim USB-PD they mean PD 2.0 which requires the CC line (Only included in usb-c to usb-c) to signal and set the voltage. When PD 3.0 is included, they usually call it quickcharge 4.0 or PPS.

Re: So Where’s My Low Voltage DC Wall Socket?

#46

Post by MisterTea »

We don't need DC sockets as they dont solve any problems. The stupid simple AC mains distribution system is well tested and proven. Who cares that they provide up to 3kW. The "last meter" problem is perfectly solved using AC-DC wall warts and bricks. If the power supply dies, you buy a new one and just plug it in. No electrician required. Putting things in wall or central distribution is not a solution to any existing problem and introduces needless cost and complexity.

A better solution would be to get everyone on board with a single DC voltage and connector. Then we can buy larger multi socket bricks that are just AC-DC power strips. You can then add batteries and give it UPS functionality. But good luck getting everyone to agree on a single standard.

Re: So Where’s My Low Voltage DC Wall Socket?

#47

Post by mumrah »

mark-r wrote: post #44
nickhalfasleep wrote: post #2

No mention of Power-over-ethernet?

What is the maximum power provided by PoE? Wikipedia is surprisingly vague on the subject, probably because there are multiple standards. PoE was never intended to power more than just network equipment.

I think it's something like 30W over a single ethernet cable. I'm running a few devices with PoE that are not network enabled, just conveniently located near an ethernet cable that's not near a power outlet.

Re: So Where’s My Low Voltage DC Wall Socket?

#48

Post by steve19 »

mark-r wrote: post #44
nickhalfasleep wrote: post #2

No mention of Power-over-ethernet?

What is the maximum power provided by PoE? Wikipedia is surprisingly vague on the subject, probably because there are multiple standards. PoE was never intended to power more than just network equipment.

I am not sure how Wikipedia can be more explicit, they even have a table showing the voltages and wattages of the different standards. [0]

According to that table, the latest standard, 802.3bt Type 4, can provide 71 W to the device at the end of the cable (and inject 100W into the otherside).

[0] https://en.wikipedia.org/wiki/Power_over_Ethernet

Re: So Where’s My Low Voltage DC Wall Socket?

#49

Post by atourgates »

unilynx wrote: post #38

If none of the current plugs are usable, can we have a low-power plug standard based on PoE? Having both ethernet and low power from one socket would be perfect for IoT devices, save people from having to run Ethernet wiring themselves afterwards, and cut down on wireless spectrum use. And your 'smart fridge' would just plug into both outlets and use a relay to cut 230V if the motor doesn't need to run.

Wouldn't the labor/effort cost to run and terminate Ethernet vs. 120v wiring be significantly higher?

My perspective is just that of someone who's run a bit of both at an amateur level through my house, and finds terminating stupid-simple 120v wiring much, much easier than ethernet.

Re: So Where’s My Low Voltage DC Wall Socket?

#50

Post by zamadatix »

lostlogin wrote: post #31
Johnny555 wrote: post #12

Earlier quoted context omitted.

If you want one port that can charge multiple devices of varying needs safely, you need smarter cables. Sounds like a reasonable tradeoff. Otherwise every single cable would have to be built to handle the highest possible power delivery rate (100W for USB-C).

Looking at that plug and how chunky the holes are for ac power, when access is limited and you can’t see, shoving a usb c plug into the ac hole is going to happen often.

The long vertical slot you could come in contact with is neutral. The bottom peg is ground. The top right vertical strip is hot but it also has recessed connectors and is smaller than the usb c connector.

I'd be impressed if you could cause a short on purpose with significant force let alone fumbling in the dark.

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