spurred light problem

[sandram9898]

Hi,

Just a bit of advice needed. I am in the middle of trying to put a light in the loft. I have spurred off a bedroom light, I know all wiring appears to be correct but the problem is that when the bedroom light is off and I turn the loft light on they both come on at half power. If I turn the bedroom light on the loft light does not work and the bedroom light is back to full power.

Any help glady appreciated, thank you.

 

[holmslaw]

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[sandram9898]

Hi, tried that but have just noticed that the 2 cables are the switch cable and the light from the bedroom, I used the switch cable as this was the only cable visible in the loft as the loft is boarded.

We do have 2 sockets that are live in the loft can we use one of them if we use a 5amp fused spur.

Thanks

 

[holmslaw]

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[Chri5]

A 3 amp fuse would be better, can you could use 1.5mm TE either side of the fused spur.

 

[holmslaw]

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[mfarrow]

And 1.5 cable is too small for spurring off a standard power circuit.

433.2.2 and 433.3.1(ii) say otherwise, however is it's a final ring circuit the specifics of 433.1.5 would mean 1.5 is unacceptable.

 

[holmslaw]

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[sandram9898]

Job now all done thanks for all your help holmslaw.

 

[holmslaw]

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[mfarrow]

First of all this a diy site, and the answer I gave the op is 100% correct because it covers all possible configurations of the existing power circuit.

Which are limitless. How do you know you're not suggesting a contravention of 433.1.5? Or even 411.3.2.2? Or section 525?

And then two people introduce nonsense replies that in no way assist the op. More importantly the replies are based on using some words that they like and ignoring words they don't like.

In what way did my reply make no sense?

Or, to put it another way " I want to do something that I think is incorrect and defies logic, but if I can find some words in the regs that make it seem correct, it will be ok"

There are so many assumptions and insults in there that it's not worth bothering to see whether it can be turned into a question. All I did was politely suggest that you may not be correct in your assumptions and you start mouthing off. Grow up

433.2.2 and 433.3.1(ii) say otherwise,

Do they really, well ony if you ignore the conditions laid out in section 434, both of the regs you quote actually state that they depend on compliance with sect 434. Read all the words, not just the ones that suit you.

Read my reply. You gave a blanket statement that 1.5 was too small, to which I gave two regulations for which it may be permitted. In no way did I say to ignore any of the wording in those regulations, including reference to section 434.

A 1.5 cable will take 272A for 0.4 seconds, assuming the breaker take that long to trip. If the circuit was designed properly, this may be sufficient for a B32 breaker under fault conditions, and again may be sufficient for a B6 breaker. But this is dependant on the PFC and characteristics of the protective devices. Have you got that information holmslaw?

All a bit academic anyway seeing that 2.5 T&E has a 1.5 cpc in itself.

however is it's a final ring circuit the specifics of 433.1.5 would mean 1.5 is unacceptable.

But if its a ring its unacceptable, what sort of circuits do you normally find in houses?

And if it was a 20A or 32A radial, would that be acceptable or unacceptable? I'll answer for you, it would be totally unacceptable.

It is you choose to ignore the regulations that apply and only read the ones you want.

The simple fact is, regardless of our debate as to what I was saying in my reply, the OP has gone away and may have extended a double spur off a ring circuit, which is 1/2 mile away from the consumer unit, with a poor main earth. But I guess we'll never know that now, or how many people died in the fire.

 

[holmslaw]

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[mfarrow]

My advice complied with 433.1.5.
I have no reason to believe that the power circuit does not comply 411.3.2.2, do you have reason?

Yes, you didn't ask him to carry out basic checks like making sure the socket he's connecting to is actually on the right part of the ring, or to undertake testing afterwards to ensure it complies.

Ah, I think you're one of those savants who can see invisible words, perhaps one too many anti ism courses.

No, they're all there, you just have to rearrange them if you want to call me illogical and wreckless.

In this situation how would you make 1.5 cable comply.

I didn't say it would. Read my words again: you said it wasn't permitted, I pointed you towards regulations stating it may be permitted depending on circumstances. As in possibly, maybe, might be, etc.

I've given advice to a diy spark who came here because he had made a mistake about a light in his loft. I admit he should have got permission from the national grid just in case he might overload the power station.

No, but to check the basics and carry out inspection and testing afterwards would have been prudent advice.

For the benefit of all of us, please advise what you would have told the op to do.

I didn't tell the OP to do anything in this instance, and I still don't didn't intent to. However seeing as you took a one line post and pulled it apart by saying I didn't know what I was talking about, instead of having an intelligent discussion, I thought I'd do the same.

 

[ban-all-sheds]

However seeing as you took a one line post and pulled it apart by saying I didn't know what I was talking about, instead of having an intelligent discussion, I thought I'd do the same.

That's what holmslaw does.

He thinks it benefits the forum.

 

[holmslaw]

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