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Sloop John B

Hi there

My enquiry is to do with lamp flex and voltage parameters. I want to buy flex from China, vintage look, multi coloured casing etc, and it states..
1..Certified SAA, VDE, UL
2..operating voltage 100-300v

If I am going to sell table lamp products in the UK, where I live, will I need China to specify that it is BSI Kitemarked, and/or has the CE marking. If it does, then should I use a specific voltage, or is anywhere between 200-300v ok?

Cheers Guys
 
If the cable is certified to VDE standards then this is a European classification and should at least meet EU requirements.
However do note that many Chinese companies may falsely claim VDE approval .
As the manufacturer of your product you are responsible for compliance with local regulations, so it important to be sure of your claims.

Presumably any mains supplied product you make for the UK will be powered by a nominal 230V ac supply so the voltage used will be defined by the supply. A 230V ac supply would be suitable for this cable according to their specification.

However do note that generally in the UK basic British standard power cables are generally 300/500V rated.
 
Thank you Richard,

Great answers, very to the point...I spent all day last week phoning electricians and on the internet and couldn't get clarity. May I ask further questions as I think you are person to ask.

'SunYe' seem to be the biggest manufacturer in China, ( hence the world? )...would I be right to assume they don't need to cheat?

If I ascertain they are legit and do comply with EU requirements, can I thus be sure that EU is ok in the UK? Does the EU mark satisfy the CE requirements; are they the same?, thus a VDE mark is as good an authority?

So the voltage in the UK is 230v ac, and if this is the current passing down a cable that is 200v, does this have an effect on the lifetime of the (thinner) wires? Would this effect the brightness of the bulb used?

When you say that 'british standard power cables' in the UK are generally 300/500v rated, do 2 core 'flex' come under the category of said 'power cables'? Kind regards John.
 
Your voltage rating for the cable should be rated higher than the voltage to be used, I would be using a cable with a minimum of 300v / 500v

When you see 2 voltage figures this relates to Uo - phase to earth and U - voltage between phases. In your case then you need the first figure to be 300v to be suitable for use, I also would be very sceptical of ordering direct from china, there are many big industries over there who owe there success to basically selling below standard cheap fake copies and claiming all standards are met.

I would source your cable from within the EU market unless you can get solid independent confirmation, that way you have a certain guarantee otherwise I would be flying out to china to personally inspect the factory and its products if this is a big venture, because your importing it and using it then it will lay on your shoulders to ensure that it is compliant to the UK market and as china is not part of the EU then any fraud on there part will still fall at your feet.

Your original query about the cable rated 200v / 300v is thus not suitable, the votage rating is related to the insulation value (di-electric strength) and even though the mains voltage you are using is 230v this in itself is misleading as this is the RMS value (root mean square) and the peak voltage would be approx 320v although the cable with a rating of 300v is usually the RMS value and it will be able to cope with the given peak voltages.

In a nutshell - you need a cable with the lower of the 2 ratings to be about 300v which is a manufacturing standard rating and this will be fine for 230v ac mains.
 
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I would agree with Darkwood that EU sourcing is a better approach.
For a manufacturing operation I would not assume anything, check and get verification at all stages.

Just for reference this is a webpage for a flexible PVC cable which would be made under the same standards as a decorative cable, this gives a voltage rating of 300V.
Also, by chance, read the note toward the bottom of the page, this is what we are also talking about, purported compliance.

If you can definitely confirm that the cable does comply with CE standards then this is suitable for use in the UK.
The size of the copper conductors affects the current rating of the cable.
The strength of the insulation affects the voltage rating of the cable.

For a domestic lighting application you would be unlikely to use a cable that would affect the brightness of the lamp, however you could use a cable that would overheat or not be insulated enough to be safe for use and could cause a risk of electric shock.
 
I think I would certainly go with a cable/flex that was rated to 500v. There's an electrical supply fault whereby a neutral becomes open circuit which can cause up to 380/400v on an electrical installation that's normally 230v. Granted, this is a once in a blue moon fault condition but it's something most electricians will have encountered.

As electricians we worry more about whether wire sizes/cable sizes in any part of a circuit are large enough to allow sufficient fault current to flow in the case of a short circuit that the protective device would trip. It might sound a bit backward to a non-sparky but if there's a short we want it to be a big one so the circuit breaker or fuse disconnects the circuit quickly. Thin flexes can cause slow disconnection times under fault currents or even not allow enough current for disconnection to take place which is a fire hazard. Even in the UK where the plug is fused, in real life most people only use 13A replacements so I'd suggest you don't go below a flex size of 1mm sq regardless of how low your load current is for these reasons. Also 0.75 and 0.5 mm sq flexes are very prone to accidental stretch damage.
 
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If you want to sell in the UK, finished products must meet EU standards. You need to certify this, not the suppliers of the components, either by constructing the technical file yourself or by outsourcing the certification process. Buying parts with CE marks on does not make the finished item CE-marked, you have to do this for each type of product you make. Therefore you must research all applicable directives for your product (e.g. Low Voltage Directive) and any constructional standards that the marketplace expects, and determine suitability of components to meet those directives and standards. Only then can you say whether a component is suitable.

FWIW, lighting products for EU sale are normally fitted with 0.75mm² flex. Double-insulated appliances often have the popular flat sheathed 2-core HO3VVH2-F, 300/300V rated and made to IEC60227-1. Larger CSA is not necessary for normal usage, smaller is generally non-compliant. But if you had special temperature, mechanical or flexure requirements this cable might not suit, and only you can determine that.

Unless you have a fully equipped goods-inwards test and qualification facility, I'd agree with the above advice and source within the EU. I have recently been screening out non-compliant parts even from reputable manufacturers where their Far-East subcontractors have realised they can get away with substituting un-approved but similar products at the final stage before the customer takes delivery.

Even in the UK where the plug is fused, in real life most people only use 13A replacements so I'd suggest you don't go below a flex size of 1mm sq regardless of how low your load current is for these reasons. Also 0.75 and 0.5 mm sq flexes are very prone to accidental stretch damage.

I don't know what you're doing to your flexes over there Marvo, but here in You-Rope 0.75mm² is the most common cable for small appliances and lighting. I've just checked about 30 double-insulated electronic goods in my workshop and every single one is 0.75. 3-core appliance cables are a mix of 0.75 and 1.0, both may be fitted with 13A fuse unless used as extension cables that can be overloaded by the user.
 
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Is there any UK 'registration of overseas manufacturers' or similar that I can check certification of the quality of their products with?
 

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