I can't see the point

[Phil Pascoe]

of sockets with usb ports, she said.

 

[HappyHacker]

I can see the point but absolutely hate them. I dislike any electronic equipment in mains wiring but unfortunately it is now standard. RCDs usually have instructions saying disconnect before insulation testing, electronic light switches and dimmers usually get upset when testing at 500V and the USB chargers are no different. Also how long will all these electronics last? I used regularly work on installation over 60 years old, all perfectly safe and with many years of life left, especially with a new consumer unit and RCDs fitted. How long will all these built in electronic devices last? How long will USB be the main standard, I cannot see it lasting 20 years? Built in obsolesce. When fault finding they can make life difficult if you have not found all the electronic devices, at least with RCDs you know where they are.

The only evidence I have is the failure rate of RCDs with electronics in them which is about 5%.

 

[Spectric]

I personally do not like them, I would much rather used a known branded USB charger plugged in only when needed and in a location of my choice. On a plus point provided the socket is a decent brand from a reputable outlet then it could reduce the number of people using these cheap asian firecrackers that we see and reduce domestic fires.

 

[Spectric]

How long will USB be the main standard

I don't think the communication protocol is an issue here but rather the physical connector, ok so far the A type on one end has held but as you say for how much longer, we just do not like standards . My issue with this type of supply is that there is no real isolation between the 230 volts and the output, these switching supplies do not use a transformer that would provide a level of isolation.

 

[akirk]

I have them in my library (office) / the kitchen we have just done, and all around the shed and workshop...
love them...
eventual redundancy is not an issue - just replace the faceplates
never had an issue with them
hugely convenient
why would you not have them?!

 

[Agent_zed]

I do have one in my house that I added but I am slightly nervous it. In the back of my mind it just seems like something else that has the potential to catch fire.
I think it's because I can't turn it off. I don't tend to charge things overnight so with the plug in chargers I can be sure it is off. If they did one where I could isolate the usb and switch it off that would be good.

With a green hat on I wonder if it is a good thing to have from a power usage point of view. They use <= 0.5watts but even that does add up if you times that by the 25million houses in the country. Seems like a lot of wasted energy for something sitting there doing nothing, although maybe not in the grand scheme of things.

 

[akirk]

decent wiring
decent equipment to plug in
decent switchboard with RCDs etc.
don't see an issue
we have things that have been plugged into those USB sockets for 3+ years and no issues

of course if the wiring is dodgy, or a charger has been bought cheap on ebay / Amazon, then you might have issues

 

[paulrbarnard]

We have lots of them. I’m just in the process of swapping some out for higher charging current and USB-C connectors.
The problem we had before was finding the plug in chargers some people have increasingly short memories . My life has become infinitely easier now as the wall sockets can’t be moved to another room, though I still have to explain that it isn’t the socket that’s the problem it’s the lightning cable plugged in to the USB-C sockets that stopping her iPad from charging.

 

[Agent_zed]

decent wiring
decent equipment to plug in
decent switchboard with RCDs etc.
don't see an issue
we have things that have been plugged into those USB sockets for 3+ years and no issues

of course if the wiring is dodgy, or a charger has been bought cheap on ebay / Amazon, then you might have issues

yeah I've had one for about 5 or 6 years and no issues. Just one of those odd unfounded worries i guess. Same old joke with why we unplug certain electronics that we clearly don't trust when we go away but trust the fridge and freezer not to burn our houses down.

 

[Noel]

It was deemed good practice a few years ago to have only one USB per socket, single or double. Concern with overloading if a kettle and/or a high draw appliance were all used at the same time.

 

[Ozi]

My tenants all like them and it lets me put them in a place where if an item catches fire when charging it is unlikely to spread, plus they tend to come on good quality sockets, I have had to have a lot of cheaper socket faces supplied by builders replaced. I have a few at home, they stop my kids stacking to many plugs

 

[nickds1]

...My issue with this type of supply is that there is no real isolation between the 230 volts and the output, these switching supplies do not use a transformer that would provide a level of isolation.

You totally sure about that? They tend to be all small SMPSs so have galvanic isolation in the transformer. I'd be interested if you could find a UK-approved (GENUINELY approved, that is. Not some knock-off with random BSnnn stickers on it from some of the well-known Far-Eastern sites) that did NOT use an SMPS with associated transformer. Yes, all SMPSs rectify the mains and then chop it, but they all tend to have an isolation transformer, plus associated protection circuitry. Feedback is by an opto-isolator, so there should always be complete galvanic isolation on such devices.

My main issue is that USB-A/B connectors, and USB-2 in general is fading into the dim and distant past very rapidly. USB-C & USB 3.x with PDv2 is absolutely what's happening now and even that will most likely change in a few years. PDv2 is essential for modern devices to charge rapidly at up to 100W (with appropriate cables). PDv3 is even more flexible (but not that common yet).

Frankly, I wouldn't ever consider USB ports in a wall socket. Just an unnecessary complexity and something else to go wrong and out-of-date. The whole wired-charging business is fraught with possible points of failure. Bring on proper contactless charging.

 

[HamsterJam]

We have an Alexa permanently plugged into a USB socket the kitchen. Leaves the 13A sockets free for other stuff. Also stops anyone running off with the charger

It was deemed good practice a few years ago to have only one USB per socket, single or double. Concern with overloading if a kettle and/or a high draw appliance were all used at the same time.

In theory I could plug two 3kW devices into a double socket, drawing a total of 6kW. I suggest an extra 20-30w to power two USB sockets is next to nothing in comparison.

 

[Terrytpot]

Generally like the idea although not all together impressed in the quality of some on sale at places like Screwfix. We had 4 installed in the last year of which 2 have already failed

 

[Sachakins]

Looking to add some in workshop and house.
Is there any particular brand that is both safe and reliable.
Always wary of the unknown factor of some of the "cheap unmarked imports"

 

[Oldman]

Just a quick google https://www.electricaldirect.co.uk/...pe-ac-usb-socket-with-2-x-usb-3a-white-809983 Lots of other UK recognised brands available.
You now get to chose between type A or C usb sockets.

 

[RogerS]

...On a plus point provided the socket is a decent brand ....

So not one made by Knightsbridge then ? We kitted out the entire house with their Pure range of low profile sockets and light switches. Marketed solely by TLC-Direct. I've lost count of the ones that have fallen apart or more spectacularly gone off with a flash and a bang when you turned the switch off ....without a load !!...tripping the RCD. Wouldn't touch their stuff with a bargepole.

 

[Spectric]

You totally sure about that? They tend to be all small SMPSs so have galvanic isolation in the transformer.

That is why I said a decent brand and it depends upon the topology of the smps as many use a buck convertor which does have a large inductance that can look like a small ferrite transformer. Also even when not in use they must still consume some power albeit very small.

So not one made by Knightsbridge then ?

Knightsbridge, Scolmore, Mk, Bg and Varilight are all good, it is the unbranded ones you come across at rock bottom prices that should be avoided but too many will buy just on being cheap.

 

[nickds1]

That is why I said a decent brand and it depends upon the topology of the smps as many use a buck convertor which does have a large inductance that can look like a small ferrite transformer. Also even when not in use they must still consume some power albeit very small.

The general rule (so I was taught) with buck converters is that the input should be no more than about 40V or so above output.

I would have thought that using a buck topology for a mains-driven USB charger would be insane. If the FET fails, you get half wave rectified mains direct to the output; this will blow up the smoothing capacitor plus anything plugged it.

The same would happen if the switching controller stopped; if it stops "on", the FET melts and we get the same result as above, likewise if the controller fails "off".

In fact there's no safe failure mode for a buck converter in this use case, except maybe the diode or inductor failing open circuit.

Basically a buck SMPS isn't much cheaper than a galvanically isolated flyback design - the magnetics are a bit more complex but the component count is pretty much identical. Why do it? Plus, a conversion ratio of 45:1 is going to make for a noisy convertor.

many use a buck convertor

Are buck converter mains socket USB supplies actually a "thing"? Has anyone seen one?

As I mentioned before, these sockets are not well suited to modern devices. Just having a USB C socket does not imply PD charging, and most seem limited to just a 3A or so shared between the sockets, i.e. 15W rather than the 60-100W a modern stand alone PD charger will deliver, so painfully slow.

We use normal sockets but with an Anker 65W USB-C & A PD charger:

Anker USB C Plug, 543 (65W II), PIQ 3.0 & GaN 4-Port Slim Fast Wall Charger, with Dual USB C Ports (45W Max), for MacBook, USB C Laptops, iPad Pro, iPhone and More

Charges up to 4 devices pretty much as fast as possible. With the A sockets, we can plug in a lightning, Garmin or whatever short lead to charge anything traditional.

Plus you can take it on holiday and one charger does everything.

Note: To use a PD-enabled charger to it's max, you'll need USB cables that can take the power and signalling - older USB cables often top out at around 15W, so watch the power capacity of the cable, especially long ones (over 2M).

 

[RogerS]

That is why I said a decent brand and it depends upon the topology of the smps as many use a buck convertor which does have a large inductance that can look like a small ferrite transformer. Also even when not in use they must still consume some power albeit very small.


Knightsbridge, Scolmore, Mk, Bg and Varilight are all good, it is the unbranded ones you come across at rock bottom prices that should be avoided but too many will buy just on being cheap.

Knightsbridge Not in my experience as I explained aboe., Whole house really needs replacing with something of quality. NOT anything from Knightsbridge given my experience with their Pure range (now discontinued...I wonder why).