One Way Lighting Circuit

[spark-doctor]

If you wanted to add another lamp to the circuit, just run another piece of T&E from the ceiling rose to another lamp. Connect the new neutral to the existing neutral. The new phase to the switched phase (the one with the sleeving and the new CPC to the existing CPC This is called the "loop in method"

 

[Bane]

Loop in method. Ok.

And the cable used is T&E 2.5mm? 1.5mm?

Phase is Live?
CPC is Earth?

Getting to grips with terminology too.

 

[ian.settle1]

Loop in method. Ok.

And the cable used is T&E 2.5mm? 1.5mm?

Phase is Live?
CPC is Earth?

Getting to grips with terminology too.

1.5mm for lighting
2.mm for sockets

 

[spark-doctor]

Loop in method. OK.

And the cable used is T&E 2.5mm? 1.5mm?

Phase is Live?
CPC is Earth?

Getting to grips with terminology too.

Generally lighting circuits are in 1.0mm T&E, socket circuits are in 2.5 T&E.

Try to get out of the habit of calling the Phase live and the CPC earth especially the later. They have different meanings as you will find out in the next few weeks

 

[Bane]

Thanks guys.

So in T&E you have:

Neutral
Phase
CPC = Circuit Protective Conductor (Earth sleeving?)

Correct?

Finally, in the diagram we'll have 1.5 going into the light fitting from the CU and 2.5 coming down to the switch?

 

[GAZHUDDS]

no you would wire all the circuit in 1.0mm or 1.5mm

 

[Bane]

Right.

Last week at work I'm sure we did all the lights in 1.5 and switches in 2.5 (Or vice versa).

 

[wayne]

shouldn't change cable size unless goihg through a fuse/mcb ...unless the original CPD is rated small enough

one way switching; from the source(mcb/fuse) to a switch through the sw to the light .neutral taken direct to the light .

17th edit is line not live

just thought i'd join in

 

[Bane]

Cheers and Hi Wayne

Can someone explain to me then, why the N becomes Live in one way then, when converted to 2 way. There is effectively 3 Live wires???

 

[spark-doctor]

You only need to switch the line/phase wire, so you use the neutral wire as a return path from the switch to the lamp.

 

[andy8758]

Hi Bane - After reading this thread - is this an obscure wind-up? Are we really discussing how one-way and two-way switches work?

Doesn't everyone know the IEE change the name of the 'Live' every 5 years to keep everyone on their toes? As we move from Phase to Line I understand that for the next version of Regs we will be calling it "Le Bang" apparently part of European Harmonisation.

OK Bane, maybe you are a student, but I thought wiring lighting circuits was covered in week 1 of your apprenticeship? Meanwhile the other guys have given you the answer so I guess I shouldn't take the mickey any further.....

lol!

 

[GAZHUDDS]

The black cable that is going to the switch is not a neutral its the switch wire or one of the strappers. By the way a neutral is always considered a live cable thats why we use terms like 'phase' conductor, remember that for college

 

[Bane]

Andy8758? Yes, the moon really is made from cheese.

GAZHUDD. Cheers for that

Is the Neutral always the return path then?

 

[GAZHUDDS]

The neutral is the return path from the load in this case the light fitting.

 

[Bane]

Got it.

Power comes down the Phase.
I press the switch.
Power returns via the N (hence the sleeving) and powers the lamp.

Phew! Now, let someone tell me that's wrong