The IET is carrying out some important updates between 17-30 April and all of our websites will be view only. For more information, read this Announcement

Rules and Guidelines
Want to participate in the discussions? Please read our Community Rules and Guidelines. Need some help? Visit Support and Answers.

  • State Not Answered
  • Locked Locked
  • Replies 13 replies
  • Subscribers 31 subscribers
  • Views 5501 views
  • Users 0 members are here
Options
You may also be interested in
This discussion is locked.
You cannot post a reply to this discussion. If you have a question start a new discussion

USB charger Euro modules

Arran Cameron
There have been a few discussions about 13A sockets with integrated USB charger sockets on the IET forum:

http://www.theiet.org/forums/forum/messageview.cfm?catid=205&threadid=62015
http://www.theiet.org/forums/forum/messageview.cfm?catid=205&threadid=63973
http://www.theiet.org/forums/forum/messageview.cfm?catid=205&threadid=63849
http://www.theiet.org/forums/forum/messageview.cfm?catid=205&threadid=84094
http://www.theiet.org/forums/forum/messageview.cfm?catid=205&threadid=104243

An alternative to a 13A socket with integrated USB charger sockets is a USB charger Euro module which can be powered via a spur from a standard 13A socket nearby. This offers several advantages over a 13A sockets with integrated USB charger sockets.

1. The USB charger module can be upgraded to a newer standard or replaced if faulty at a lower cost than a 13A socket with integrated USB charger sockets.
2. It’s possible to mix and match modules and faceplates from different manufacturers. A module that is considered the best performing or most reliable from manufacturer A can be used with a faceplate with the desired aesthetics from manufacturer B.
3. A switch can be added in series with the module to isolate it from the mains supply.
4. USB charger modules can be powered from a dedicated circuit rather than the ring main.

A few questions:

1. Has the IET done any reviews of USB charger modules from different manufacturers?
2. Are USB charger modules internally fused or is it recommended that they are connected in series with a (1A?) fuse? Fused Euro modules exist which could be installed on the same faceplate as a USB charger module.
3. Do the wiring regulations permit USB charger modules to be powered from a lighting circuit? I have thought about mounting them on the same faceplate as a light switch for the room. I am aware that the cable from the ceiling rose to the switch requires a neutral wire although some already have this.
4. Is it true that the wiring regulations do not permit mains powered Euro modules to use the same faceplate as low voltage (telephone socket, TV antenna, etc.)Euro modules?
  • 0

    1. Has the IET done any reviews of USB charger modules from different manufacturers?



    Not that I'm aware of


    2. Are USB charger modules internally fused or is it recommended that they are connected in series with a (1A?) fuse? Fused Euro modules exist which could be installed on the same faceplate as a USB charger module.



    That is up to the manufacturer, and how they choose to comply with BS EN 60950-1, BS EN 62368-1 or other means of complying with the Electrical Equipment (Safety) Regulations (or in the case of a module within a BS 1363-2:2016 socket-outlet, the requirements of BS 1363-2)


    3. Do the wiring regulations permit USB charger modules to be powered from a lighting circuit? I have thought about mounting them on the same faceplate as a light switch for the room. I am aware that the cable from the ceiling rose to the switch requires a neutral wire although some already have this.



    There is I suppose nothing to exclude them from a safety perspective, but dependent on the luminaires being used on the circuit, there may be EMC issues? (Not all lighting circuits are "domestic").


    4. Is it true that the wiring regulations do not permit mains powered Euro modules to use the same faceplate as low voltage (telephone socket, TV antenna, etc.)Euro modules?



    Separation is required as necessary for electrical safety. For example, to prevent a broken Band 2 conductor connecting accidentally with a Band 1 terminal.


    But a "mains in the back, ELV out of the front" solution may be OK to share with another Band 2 device, provided there are no segregation issues on the output sockets.
  • 0

    4. Is it true that the wiring regulations do not permit mains powered Euro modules to use the same faceplate as low voltage (telephone socket, TV antenna, etc.)Euro modules?



    I addition to Graham Kekyon's answer, if you are mixing different voltages in the same compartment (for instance mains and ethernet), then enerything in that compartment must be insulated to the highest voltage present.


    Ethernet or telephone cables don't have mains voltage insulation as standard.
  • 0

    Graham Kenyon:


    Not that I'm aware of

    I'm a bit disappointed to read this. I was expecting the IET to have carried out an investigation into these USB charger modules as they are permanently wired into buildings as opposed to being a plug-in consumer product.

    Separation is required as necessary for electrical safety. For example, to prevent a broken Band 2 conductor connecting accidentally with a Band 1 terminal.


    But a "mains in the back, ELV out of the front" solution may be OK to share with another Band 2 device, provided there are no segregation issues on the output sockets.

    Electrical accessory manufacturers sell plates consisting of 13A sockets with holes for Euro modules. They are colloquially called lounge plates presumably because they are designed to be installed behind a TV and contain Euro modules for TV antenna, satellite, HDMI, audio and video, and Ethernet. Do these violate segregation rules?
  • 0

    I'm a bit disappointed to read this. I was expecting the IET to have carried out an investigation into these USB charger modules as they are permanently wired into buildings as opposed to being a plug-in consumer product.





    An interesting perspective, but perhaps there is another perspective.


    The socket-outlet itself is merely a consumer product. One containing an integral USB charging outlet is covered by the same British Standard, BS 1363-2:2016. This standard is managed by BSI Technical Committee PEL/23. The Wiring Regulations, to which I'm assuming you are referring based on the IET's involvement, is BS 7671, and this standard is managed by the joint IET/BSI Committee JPEL/64.

    BS 7671 requires generla 230 V socket-outlets for domestic and similar use to comply with BS 1363-2, and this would imply that those containing a USB charger comply with BS 1363-2:2016.


    To the best of my knowledge, BS 1363-2:2016 requires the USB charger to comply with a suitable British Standard such as BS EN 60950-1 for electrical safety.

     

    Electrical accessory manufacturers sell plates consisting of 13A sockets with holes for Euro modules. They are colloquially called lounge plates presumably because they are designed to be installed behind a TV and contain Euro modules for TV antenna, satellite, HDMI, audio and video, and Ethernet. Do these violate segregation rules?





    That depends on whether you install it as per the manufacturer's instructions and maintain segregation of services at different voltage bands (or to maintain SELV/PELV) in accordance with BS 7671 - also depends on whether you mix Band 1 and Band 2 modules in the same "compartment".


    (NOTE: links below for convenience and to illustrate a point, not a preference of supplier or manufacturer)


    e.g. with this plate: https://www.screwfix.com/p/british-general-13a-2-gang-combination-plate-white/7425f

    the manufacturer recommends this backbox: https://www.screwfix.com/p/british-general-mounting-box-steel/5072f?_requestid=249404


    As you will see, the backboxes for both parts are actually physically segregated, so provided you keep the "mains" wiring in the socket-outlet box, and reserve the EuroMod box for Band 2 (audio / video / broadcast RF / data), there should be no safety problem. In terms of wiring in the "safe zones" to the accessory ... well, there's nothing to prevent you providing plastic or metal conduit in one or the other box as necessary to pass a cable through of the other voltage band?


    So, if you are talking about putting a USB EuroMod module in one of these plates, I think the manufacturer would not recommend that if there are Band 2 circuits (audio / video / coax / data) in the same backbox - and you'd certainly need to be careful for BS 7671 compliance.
  • 0
    Is there a standard or recommended arrangement of wiring USB charger modules in a building? Four possible arrangements are:


    1. As part of the ring main.

    2. On a spur from a socket on a ring main. Do the wiring regulations permit more than one (on different faceplates) USB charger modules to be connected on a spur from a socket? 

    3. A separate ring main.

    4. Radially wired.


    In the case of 3 and 4 then is 1mm2 cable and a 6A MCB acceptable?
  • 0
    Considering separate modules only, this depends on the manufacturer's requirements for protection - similar to a manufacturer of an extractor fan requiring them to be supplied by a 1 A fuse in an FCU, but another manufacturer not?


    Unlike switches and socket-outlets, I don't think you'll find a unified approach.


    Clearly, this one from MK could be installed on a radial or ringmain protected by a B32 or C32 (see section F of the instructions) ... if you look at the specs, it will accept 3 x 2.5 sq mm as well.


    But this one from BG cannot simply be wired "in the ring" or anything other than the last device in a radial, given the terminal capacity 1 x 2.5 sq mm or 1 x 4 sq mm - even though the specs I can see don't have the info on what maximum rating protective device is recommended - I'm suspecting that the


    If the module is built into a socket-outlet to BS 1363-2:2016 (or BS 1363-2:2016+A1:2018), then the ratings and installation method should be as per BS 1363, i.e. should be OK for a radial or ringmain.


    PLEASE NOTE: I've seen on some, provision for dual earth terminals ... does this mean they might have high protective conductor currents if a number of units are installed on the same circuit (I can't see any data for this in the manufacturers' data I've looked at so far)? The particular MK Euro-Module I linked to above, appears to be Class II so probably not a problem.



    And in terms of cable size ... sized in accordance with BS 7671 as necessary for protection against overcurrent etc. with absolute minimum size as Table 52.3


  • 0

    Graham Kenyon:


    Clearly, this one from MK could be installed on a radial or ringmain protected by a B32 or C32 (see section F of the instructions) ... if you look at the specs, it will accept 3 x 2.5 sq mm as well.


    But this one from BG cannot simply be wired "in the ring" or anything other than the last device in a radial, given the terminal capacity 1 x 2.5 sq mm or 1 x 4 sq mm - even though the specs I can see don't have the info on what maximum rating protective device is recommended - I'm suspecting that the




    That's an astute finding. I suspect (expect?!) that the MK module has been designed thoughtfully so that it can be included in a ring main like a 13A socket whereas the BG module is consumer grade and assumed will be installed as a spur or a radial.


    It would be sensible for the next edition of the wiring regs to have a section for USB charger Euro modules.


  • 0
    What additional requirements should be in BS 7671?


    Surely this is simply current-using equipment complying with relevant standards? What's the difference between a USB charging module and, say, a ceiling fan, luminaire, or wall panel heater?


    BS 7671 is not really an installation manual, and even the guidance on standard ring and radial final circuits in Appendix 15 is only informative, not part of the Regulations as a whole.



    Perhaps a better place might be GN1 - selection and erection?


    What sort of information would you be looking for in guidance?
  • 0

    Graham Kenyon:


    Surely this is simply current-using equipment complying with relevant standards? What's the difference between a USB charging module and, say, a ceiling fan, luminaire, or wall panel heater?




    I suppose that USB charger modules could be treated in a similar way to fixed in appliances that are either powered from dedicated circuits with their own MCB, or incorporated into a ring main or run as a spur from a ring main on a 13A fused outlet. I can see a vague similarity between USB charger modules and clock connectors used for mains powered clocks, alarms, etc. that must not be inadvertently disconnected.


    One way to look at the question would be to think about a new building where every room has at least one USB charger socket in addition to at least one 13A socket on a ring main. How would you prefer to wire them in? 


  • 0
    I don't really have a preference technically, but personally I think I'd probably go for integrated in a socket-outlet to BS 1363-2:2016 or BS 1363-2:2016+A1:2018 from an overall environmental/ustainability perspective ... but that of course may affect insulation resistance testing. If on a radial, just keep a mind to high protective conductor currents if that's seen as an issue.


    With Euro modules, as discussed, it's the manufacturer's ratings which dictates whether it's a fused spur or a spur off the ring or radial, or whether you can use the ring or radial. If you choose a fused spur, then:

    (a) The FCU can actually go in the ring or radial

    (b) Fuse can be removed for maintenance, USB module failure, and perhaps IR testing


    I guess it's as with all these things - to a point, the more you pay, the better you get.


Join us to get the best from IET EngX.

Joining EngX lets you personalise your experience so you stay up to date on the topics that interest you, plus you’ll be able to make connections who are looking to collaborate, exchange ideas and more.

Join us Not now

Community Rules & Guidelines