I recently bought a new light fitting off amazon.co.uk which has come with wiring as shown in the picture:

Wiring of light

I'm surprised to see black/white cabling since I thought this to be the US colour coding. The listing on Amazon claims

Compatible with world wide voltage - 110V or 240V and everything in between - please make use appropriate voltage of light bulb

However, there was nothing in the box that had the usual UK standards that I would expect when purchasing anything electrical in this country, generally one would expect to see the CE symbol but the fitting came in a plain cardboard box with nothing else inside (https://en.wikipedia.org/wiki/CE_marking):

CE Symbol

How do I know that this is either meets UK electrical standards and can actually work with a 240V mains circuit? The only documentation that claims this is the case is in the Amazon product description


The CE Mark

The CE mark is an unverified promise by the inside-the-EU manufacturer ... or the inside-the-EU importer. It promises that the item complies with EU safety standards.

It is not anything like UL, CSA, TUV, etc. - those are independent testing labs and their staff has actually run a specimen of the product through a battery of tests, everything from overloads to flame-testing (for toxic substances) to sourcing of components.

You're the importer. You're responsible.

Anyway, when you buy via Amazon/ebay/Ali, you are importing this into the EU. So if it has the mark (obviously, it's counterfeit), you are agreeing to test it according to CE standards (and of course it will fail).

If it does not have the CE mark, then it's illegal to install it, unless it has the mark and listing number of a proper testing lab like TUV.

Amazon is a slippery one, because they seem like a domestic mail-order supplier like Wickes or Redoute who you would expect to be reliable. But Amazon intermixes into their listings something called Amazon Marketplace, which is a flea market of third party sellers peddling the cheapest junk in Shenzhen.

People confuse these "Marketplace" flea-market listings with listings actually sold by Amazon proper. The scammers write a bunch of fake reviews*, and often charge similar prices to quality domestic goods, and people buy it because they think the high price means quality product. They've really got it down.

The products Amazon buys for their own internal sale are usually high quality normal goods like you'd get from Wickes.

The wires

If you find a proper UL listing or equivalent, then you can install it. Due to treaties, a CSA listing on a US product is honored in the EU. (again CE isn't anything, but a TUV listing from a German product is honored in the US). So it's not uncommon to find EU color codes (brown/blue) in the US or US color codes (black/white) in the EU.

Black is hot and should be taped brown (not critical).

White is neutral and should be taped light blue.

* They get "verified sale" on their reviews thusly: Initially they direct-ship the items, place hundreds of orders from sockpuppet accounts, don't actually ship the item, collect the payment from themselves (eating Amazon's cut), then write a glowing 5-star review of themselves. Then with their 4.7 star rating, they place it in Amazon Fulfillment so it's drop-shipped from an Amazon warehouse.


How do I know that this is either meets UK electrical standards and can actually work with a 240V mains circuit? The only documentation that claims this is the case is in the Amazon product description

You don't. It probably does not (meet the standards - working on 240V is easy enough), or it would be so marked.

Heck, the vendor didn't even bother to put on counterfeit certifications (which are a bit too common for comfort.)

I would suggest returning it for that reason. Who knows how badly it's made?


So green / yellow is earth.

You can put the black to live (aka phase) and the white to neutral (based on the comment by Dan D below). You could satisfy yourself by using a multimeter to check for continuity as appropriate.

If you are still unsure, then employ the services of a qualified electrician.

As for labelling, there may be some inside the product.

For wiring colors, they vary around the world and can be seen here :

This is just for flexible cable, the chart continues for fixed cables etc, just follow the link.

enter image description here

wiring colors

  • It is black to phase and white to neutral. Otherwise If it had an Edison base the threading would hot.
    – Dan D.
    May 14 '19 at 8:42
  • @DanD. I will edit, of course, if you put your finger inside the fitting then it is easy enough to touch both anyway, which is why the supply should be disconnected even when "just" changing a bulb.
    – Solar Mike
    May 14 '19 at 8:43
  • @SolarMike it’s more important than “finger in the socket”. If polarity is reversed the threads of the bulb remain hot while the bulb is being unscrewed. It should just take half a turn to disengage voltage when changing a bulb. Ever had a bulb break during changing process, halfway unscrewed?
    – Tyson
    May 14 '19 at 13:26
  • @Tyson you should disconnect the supply - and suggesting otherwise is not good practice... And I have had many bulbs break - but never had any cut from that happening...
    – Solar Mike
    May 14 '19 at 13:27
  • @SolarMike while I usually do personally, I can’t rely on “anybody” that might change the lightbulb doing so. This is one of many reasons polarity must be correct for an Edison socket.
    – Tyson
    May 14 '19 at 13:32

Internal conductor coloring means nothing really, although you should probably stick to the earlier recommendations; i.e. white to neutral. As to 240V or 120V, that boils down to the bulb you install, meaning that if you use a 240V rated bulb, it's 240V. The device itself (socket, switch if any) will all be "300V class" meaning clearances and insulation is good for anything up to 300VAC.

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