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
Can we clarify the use of Energy Source Classes 1, 2 and 3 for hazard levels of voltages and currents and the standards not discussing SELV, PELV, ELV and LV
If we need the USB socket to be SELV but the usual USB converters don't say they provide SELV - could we achieve the same be creating a simple 12V SELV circuit (using a conventional isolating transformer if needs be), convert to d.c. and then use a 12V powered USB module (of the type usually used in caravans or vehicles - e.g. https://www.12voltplanet.co.uk/cbe-21a-double-usb-charger-grey.html) - I can't see that the module would be able to "un-SELV" the circuit as it were.
- Andy.
What standard would the 'created SELV' system be made to? I think you'd be assembling some arrangement (you'd need individual components, such as transformer, rectifier, capacitor etc.) and then we're into realms of Regulation 113.1. The standard for a DC supply is no longer BS EN 60950-1, but BS EN 62368-1, which is where the issue of "non-alignment" arises.
I was thinking the SELV source could be to BS EN 61558-2-6 (something like this perhaps, https://uk.rs-online.com/web/p/din-rail-transformers/7720704, or maybe something less RS-priced) - I think that would then satisfy BS 7671's requirements for any specific standards for SELV systems - the remaining parts need only each need to comply with some suitable standard for each individual part. With any installation we're assembling parts complying with a wide variety of different standards - this would just be an extreme example of the same principle. If people don't fancy soldering together diodes, capacitors etc on site, ready built 12V AC to DC converters are available (e.g. https://www.autodoortrader.co.uk/12v-ac-dc-converter-1076-p.asp - but check standard compliance of course)).
- Andy.
What i need to offer is a solution so no soldering or building on site.
I need to consider real world risks to the client and their customer, not just be approved. With what im understanding is that an approved setup could still be fatal in the right situation. Limiting voltage to lower limits I.e 5-12v output, isolated supply and IP rating (marine) USB connector.
Although my first choice will be to discuss installing outside zone 2
Although my first choice will be to discuss installing outside zone 2
I am not sure that helps. As Andy has already mentioned, unless the supply is SELV, no socket-outlet is permitted within 2.5 m. The definition of socket-outlet is very broad and IMHO includes USB - it is not restricted to mains voltage.
the remaining parts need only each need to comply with some suitable standard for each individual part. W
I disagree ... sub-assemblies aren't certified to suitable product standards.
Legislation also gets in the way for that type of 'assembly', including the EMC Regulations 2016.
This definitely falls into what is being covered by Regulation 113.1.
the remaining parts need only each need to comply with some suitable standard for each individual part. W
I disagree ... sub-assemblies aren't certified to suitable product standards.
Legislation also gets in the way for that type of 'assembly', including the EMC Regulations 2016.
This definitely falls into what is being covered by Regulation 113.1.
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