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Never really comment, just enjoying reading. Just wondering with all comments if 1mm is minimum allowed for lighting, how come 0.75mm flex is supplied with most pendants, surely this must class as part of the lighting circuit?
Not really fixed wiring though is it??
 
0.75 is inadequate for the purpose of fixed wiring minimum size for lighting is 1.0mm. If they have used this for the supply from the consumer unit this is incorrect and it needs replacing.

I think I have to agree with westward here.

Here's a previous thread on the subject;


Just BS7671 being ambiguous again; as @Andy78 said #57 'in table 52.3 "for any other application" listed for flex actually should mean "for any other application (other) than those listed above" .

As the above thread, a flex for fixed wiring would also need to comply with 521.9.1 (BYB), which for the OP's benefit states;

'A flexible cable shall be used for fixed wiring only where the relevant provisions of the Regulations are met. Flexible cables used for fixed wiring shall be of the heavy duty type unless the risk of damage during installation and service, due to impact or other mechanical stresses, is low or has been minimised or protection against mechanical damage is provided. Note: Descriptions of light, normal and heavy duty types are given in BS EN 50565-1'.

Great these search engines on the web.:)
 
I've also found a piece on the Voltimum web site;


again for the OP's benefit it says;

With reference to Table 52.3 of BS 7671, the minimum conductor size for a radial final circuit for lighting, protected by an overcurrent protective device with a rated current or current setting (In) of 6 A, is 1.0 mm2 for thermoplastic (PVC) or thermosetting insulated cables having copper conductors.
The flexible cable between the ceiling rose or similar and the lampholder is permitted to have a minimum cross-sectional area of 0.75 mm2 (see Regulations 433.3.1(ii), 524.1 and Table 52.3). This flexible cable should preferably have 90 °C thermoplastic insulation.
 
This install (though realistically not unsafe) is not in line with the BS 7671 so should therefore be rectified by the installer/designer because it cannot be "satisfactory" certified.
 
I have had a long trawl through the relevant sections of the BBB and cannot see anything which specifically prevents the use of a flexible cable of 0.75mm csa. None of the above, including the voltimum statement supersede what it actually states in table 52.3. It clearly states that for any purpose other than a specific appliance or ELV the minimum is 0.75mm. However if anyone else can definitely show otherwise I'll accept my interpretation is wrong
 
As its been said before, the wording in the table is poorly written and should be clearer.

If one looks at the tables for ccc, the one for flexible cables has no installation methods, unlike that for insulated & sheathed flat cable; granted there are other tables for reference methods to determine ccc.

52.3 specifically mentions lighting & power circuits insulated & sheathed cables, but then doesn't for flexible cables. Why doesn't it just say for any other application for both cable types?
 
Well I don't often disagree with @westward10 but I think @happysteve has it with this one.

Table 52.3 is very clear. You don't just jump to the 'lighting circuits' part of the table. You HAVE to start at the beginning and work your way through a table. Therefore 0.75mm is acceptable in this scenario, however much we all dislike the idea.

edit.... although I met it doesn't meet the voltage drop requirements!
 
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Well I'm sure the OP is none the wiser after this one.

I'd probably say it is OK as well. The lights are permanent LED fittings, it is not as if they are ceiling rose pendants and the low wattage bulbs can be replaced by old style incandescent bulbs.
 
Well I don't often disagree with @westward10 but I think @happysteve has it with this one.

Table 52.3 is very clear. You don't just jump to the 'lighting circuits' part of the table. You HAVE to start at the beginning and work your way through a table. Therefore 0.75mm is acceptable in this scenario, however much we all dislike the idea.

edit.... although I met it doesn't meet the voltage drop requirements!
what are you on HHD? have you been to a wholesalers lately and asked for a 100M drum of 0.75mm2 T and E with lots of qualified Sparkies' in attendance waiting for their free coffee?
 
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Well I'm sure the OP is none the wiser after this one.

I'd probably say it is OK as well. The lights are permanent LED fittings, it is not as if they are ceiling rose pendants and the low wattage bulbs can be replaced by old style incandescent bulbs.
We do tend to get a bit carried away don't we. Poor old OP doesn't know which way to turn, and also doesn't even know what OP means, so doesn't even know we're talking about him!
 
Away from the discussion about 1mm or 0.75mm, who or what sort of person would wire the garden lights in 1.5mm3 SWA cable, and then lash it on to a length of 0.75mm2 flex, answers on a post card please.
Advice on work I've had done 2f95cd854187f3c3429bcd5f2d6a8f6c--cowboy-pics-cowboy-art - EletriciansForums.net
 
Interesting discussion,I have my opinion and it agrees with one of the competing views :)

Where I see a problem is with the op in his opening post describing the cable as they have used a 0.75mm 3 core white flex cable.

He is extra observant or meticulous with his estimate of flexible cable size because on the one hand he asks question of regulations and on the other hand he is better than me at sizing the difference between a 1.0mm flex and 0.75mm flex in situ

Something does not seem to add up,the story does not seem to be fully disclosed,it could very well have been 1.0mm flex from the outset :)
 
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Interesting discussion,I have my opinion and it agrees with one of the competing views :)

Where I see a problem is with the op in his opening post describing the cable as they have used a 0.75mm 3 core white flex cable.

He is extra observant or meticulous with his estimate of flexible cable size because on the one hand he asks question of regulations and on the other hand he is better than me at sizing the difference in a 1.omm and 0.75 flex in situ
Something does not seem to add up,the story does not seem to be fully disclosed
It may say the size of the cable on the flex......but you could be right in what your thinking
 
I think what we can all agree on is, though not unsafe, it appears (assuming what the OP says is accurate) to be a bit of a bodge job. Without the full details and any pictures this is my personal opinion.
My advise to the OP is to get a honest second opinion from another qualified spark.
 
I think what we can all agree on is, though not unsafe, it appears (assuming what the OP says is accurate) to be a bit of a bodge job. Without the full details and any pictures this is my personal opinion.
My advise to the OP is to get a honest second opinion from another qualified spark.
I think a bodge job might be a bit strong description a bit orthodox maybe. Is it unsafe I don't think so but as posted without pictures it is hard to tell.
 
Interesting discussion,I have my opinion and it agrees with one of the competing views :)

Where I see a problem is with the op in his opening post describing the cable as they have used a 0.75mm 3 core white flex cable.

He is extra observant or meticulous with his estimate of flexible cable size because on the one hand he asks question of regulations and on the other hand he is better than me at sizing the difference between a 1.0mm flex and 0.75mm flex in situ

Something does not seem to add up,the story does not seem to be fully disclosed,it could very well have been 1.0mm flex from the outset :)

It says 0.75 on the cable, as well as some other letters and numbers.

I've been trying to get hold of the company but not had any luck, I said about the certificate and apparently he needs to come and take some details of the fuse board but doesn't have time to do it at the moment...apparently.

Anyway, I've arranged for another person to come and have a look at the work that's been done, when I told them about the 0.75mm cable they didn't seem impressed.
 

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