lighting circuit wiring pedantry!!

[blubs]

Can someone please show me the correct way to wire these lights, the most efficient way to pass the regulations, or the code of best practice way please.. and specify which if you can, (yes i believe there is a difference!!)
what about if the 2 lights on the left were existing, and the job was adding the 2 on the right???
It will soon be clear what i am getting us into!!!!,

 

[blubs]

an explanination in words will do, it doesn't matter if these are roses or switches , i just need 1.5mm t and e to all 4 of them...

 

[PBC_1966]

I'm not quite sure what you're getting at - Based on your rather basic sketch which, presumably, is intended to show the relative positions, then the obvious would surely be to take one cable from the CU out to the lights on the left and another out to the lights on the right? That might change if some physical aspect of the building would make it more difficult.

 

[EFLImpudence]

Well, for a start 1mm² will be more than adequate.



There are different ways in which the wiring could be done. What are you getting at?

The regulations state what must be achieved - mainly safety - they do not say how to wire things.
The best practice guides are just that - guides - written by someone with whom you may disagree and not the only way to do things.

Even the regulations are not the only way.

 

[DetlefSchmitz]

If you don't show the switches and explain what switching functionality you want then the question can't be answered.

 

[blubs]

I'm not quite sure what you're getting at - Based on your rather basic sketch which, presumably, is intended to show the relative positions, then the obvious would surely be to take one cable from the CU out to the lights on the left and another out to the lights on the right? That might change if some physical aspect of the building would make it more difficult.

yes, this would surely be the right approach using the minimum wire , BUT there seems to be a culture of, 'doubling up cables into one breaker is bad' hence my sparky, who is essentially adding the 2 lights, buying a second RCBO!! i wouldn't mind, but he won't let me have the receipt so that i can take it back and put my 1a of lighting back onto just one breaker when he's done my BS cert for building control!!!!!!

 

[blubs]

we might compromise and put a JB adjacent to CU so that he doesn't have his '2 wires, 1 breaker= bad' fear!! will save me £35!! but its extra wiring and connections that are completely un necessary!! some people just don't fully understand why they are doing what they are doing, and can't think above the guidelines!, the '2 wires bad' thing is to train sparks that can't think for themselves to spot, say, and oven and shower in one breaker!!

 

[blubs]

Well, for a start 1mm² will be more than adequate.



There are different ways in which the wiring could be done. What are you getting at?

The regulations state what must be achieved - mainly safety - they do not say how to wire things.
The best practice guides are just that - guides - written by someone with whom you may disagree and not the only way to do things.

Even the regulations are not the only way.

yes your right, and guess what, he doesn't like the idea of 1mm2 either!!!! even though my entire floor is less than 200w!!!! now split between 2 rcbo's at £35 each!!

 

[EFLImpudence]

Then I sympathise with you.

If YOU don't mind the lights on one breaker (all lost with one fault) then there is no need for another RCBO.

 

[PBC_1966]

so that he doesn't have his '2 wires, 1 breaker= bad' fear!!

Have you asked him exactly why he thinks it's bad?

 

[blubs]

He can't engage in debate about it , it's either done his way , or not at all ! I am accused of telling him how to do his job by looking up answers on mums net !! I have seen on other forums sparks getting funny about 'doubling up' as bad practice , and hilariously the "2 circuits on one breaker" claim , which of course is nonsense , it's just one circuit wired differently to how it is in the books they learn from !!
He also removed my 2 seperate 10mm2 earths , and replaced them with 1 16mm2 one! , then proceeded to rewire both the neutral bars so that the numbers matched the breakers !! , (they weren't mixed between rcd and non rcd of course) , so I am going to pay him to do all this unneccisary stuff !! Can someone part p registered please tell him if he's reading this, that these things are not necessary to conform to regs please , I don't know for sure , but I am 95% certain that it's ok to hve 2 wires in one breaker that isn't a ring , 2 times 10mm2 earth instead of 1 16mm2 earth , and the blue wires in any hole you like on the bar ??? Not saying the last two are ideal , but not contravening anything surely ??

 

[Iggifer]

Why were there two 10mm² earths? From the cutout to the consumer unit? TBH, whilst strictly the CSA of the cables would have been more than adequate, I probably would have changed it too.

As for the neutrals the right way around, again, it's proper procedure to install them in order, but unless I needed to do major testing work in there, probably not something you'd do without asking.

There's nothing in stone that says you can't run 'two circuits' from one breaker. It's absolutely no different to installing a JB on the outgoing cable before it meets anything and splitting the cable. In fact, that's exactly how I wired the emergency light above my parents consumer unit - so that if the breaker tripped, the emergency light comes on. Yes I could have wired it differently, but when it's literally above the consumer unit, why would I?

 

[EFLImpudence]

There's nothing in stone that says you can't run 'two circuits' from one breaker.

blubs is right - technically it's not two circuits. It's one circuit (Edit) with two branches.

 

[blubs]

There was 2 x 10mm2 earths because that's all I had when I wired the consumer unit 10 years ago , I actually think this is better , as if one terminal came loose , there would be back up , I didn't mind him changing this for the correct 16mm2 'by the book' earth , also , I didnt see him testing circuits , but can imagine that if he is removing the neutrals , then it makes sense to put them back in their 'correct' holes. , but the 2 rcbos for my ground floor lighting because there are 2 wires going to the CU was the sticking point !!

 

[blubs]

There's nothing in stone that says you can't run 'two circuits' from one breaker.

blubs is right - technically it's not two circuits. It's one circuit.

Thanks. I think he agrees , as he put '2 circuits' in inverted commas !