I've been asked to add a USB charging port into a bedroom with a bath in it.
My understanding of BS7671 is that a room with a bath is a bathroom. As such the outlet would be in zone 2 of the bath.
Would I need to power the charger via a safety transformer and could this be built into a +IP4 enclosure similar to a shaver outlet
Thanks for your assistance
Assuming there is no 230V socket, is not the 5V of the USB already derived by transformer inside the fitting ? (though probably a switch mode one).
Your bigger problem will be the IP rating of the USB electronics as not designed to survive steam and condensation.
I have in the past where I needed a USB socket in a wet place ( that was on a vehicle mind you) I located electronics in a separate box in the dry and extended the 5V side of things by a couple of metres with a USB extension cable .
Chasssis mounted USB sockets link to one example, can look quite smart on a suitable blanking panel. there are also modular grid socket versions both with PSU and where a USB cable comes out the back,
A variation on that theme might be worth considering with the actual supply protected either in a cupboard or outside the bathroom altogether, and just the USB cable coming into Z2..
Mike.
That was plan B.
I make special plates so I could use a simple ipx4 socket in and ipx4 plate/ back box configuration with a USB outside zone 2 or even 3. But am I allowed to embed the USB extension cable in the wall?
I also think the USB brick (230vac to usb) has to be hard wired?
Well a USB cable in the wall is an example of ELV, so arguably safer than a mains cable in the wall (!), the hardest problem will be threading it through a suitable route with the plug on, and the distance cant be too long, as the voltage drop at 5V becomes proportionally more serious. The mains to USB converter would have to be hard wired if it was in the bathroom Z2, or indeed within 2.5m of the edge of the bath or shower tray.
Outside that distance you can have a normal 13A socket. It must be said, very few modern bathrooms have that much free space, hence the advice that in effect bathrooms in the UK remain socket free zones. The easy solution may be a USB fitting in the adjacent room and a line through the wall. I'd probably use flexible conduit or something so the cable can be easily threaded.
Mike
Assuming there is no 230V socket, is not the 5V of the USB already derived by transformer inside the fitting ?
It is not always 5V anymore, I believe the first version of USB was 5V only but more recent versions and variants, particularly USB-C are now variable voltage and have communications between the power supply and the device that can raise the voltage upto 20V - 30V or more, to allow rapid charging of mobile phones, tablets or powering of laptops, while keeping the current at manageable levels.
Many laptops now use USB-C for power supplies, just from a quick search, it looks like laptop power supplies to USB-C PD 3.1 can even get upto 48V for 240W power output !
Assuming there is no 230V socket, is not the 5V of the USB already derived by transformer inside the fitting ?
It is not always 5V anymore, I believe the first version of USB was 5V only but more recent versions and variants, particularly USB-C are now variable voltage and have communications between the power supply and the device that can raise the voltage upto 20V - 30V or more, to allow rapid charging of mobile phones, tablets or powering of laptops, while keeping the current at manageable levels.
Many laptops now use USB-C for power supplies, just from a quick search, it looks like laptop power supplies to USB-C PD 3.1 can even get upto 48V for 240W power output !
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