Turning switched live into a neutral

[sparkol]

I've got a customer who wants an outside light removing and a replacement installing about 4 metres away on the same wall. The location where she wants the new light happens to be directly behind the relevant lightswitch.

Is it acceptable to do the following?:

1. Remove existing light.
2. Crimp the N to the S/L at the existing light and poke it back through the wall. This will mean that, at the lightswitch, the wires which were previously L and S/L are now permanent L and N.
3. Now that I have a permanent L and N at the lightswitch, connect a short length of wire and run it through the wall behind the lightswitch to give me power for the new light, with another short length back through the wall to give me a new L and S/L.

Obviously I would only do this if the cable tested out ok, and if I could leave it in such a way that it complied with the regs (in safe zones, etc).

The advantage would be that I avoid running a new cable along the outside of the house.

Thanks in anticipation!

 

[adammid]

Why are you running a perm live to the new light. You only need a s/l and neutral at the new light.

 

[Guest111]

Why are you running a perm live to the new light. You only need a s/l and neutral at the new light.

I dont think he's running a perm live to new light,just trying to avoid a joint and more cable clipped along the wall outside.

 

[LineProducts]

I've got a customer who wants an outside light removing and a replacement installing about 4 metres away on the same wall. The location where she wants the new light happens to be directly behind the relevant lightswitch.

Is it acceptable to do the following?:

1. Remove existing light.
2. Crimp the N to the S/L at the existing light and poke it back through the wall. This will mean that, at the lightswitch, the wires which were previously L and S/L are now permanent L and N.
3. Now that I have a permanent L and N at the lightswitch, connect a short length of wire and run it through the wall behind the lightswitch to give me power for the new light, with another short length back through the wall to give me a new L and S/L.

Obviously I would only do this if the cable tested out ok, and if I could leave it in such a way that it complied with the regs (in safe zones, etc).

The advantage would be that I avoid running a new cable along the outside of the house.

Thanks in anticipation!

The way I see it is that you are bringing both L and N and CPC to the light switch from the existing light point (same cable). So you are just extending the circuit. Providing all else complies cant see any problem.

 

[sparkol]

The way I see it is that you are bringing both L and N and CPC to the light switch from the existing light point (same cable). So you are just extending the circuit. Providing all else complies cant see any problem.

thanks!

Adammid - yes I agree it'll probably be easier to wire it in line.

 

[Deleted member 9648]

I've got a customer who wants an outside light removing and a replacement installing about 4 metres away on the same wall. The location where she wants the new light happens to be directly behind the relevant lightswitch.

Is it acceptable to do the following?:

1. Remove existing light.
2. Crimp the N to the S/L at the existing light and poke it back through the wall. This will mean that, at the lightswitch, the wires which were previously L and S/L are now permanent L and N.
3. Now that I have a permanent L and N at the lightswitch, connect a short length of wire and run it through the wall behind the lightswitch to give me power for the new light, with another short length back through the wall to give me a new L and S/L.

Obviously I would only do this if the cable tested out ok, and if I could leave it in such a way that it complied with the regs (in safe zones, etc).

The advantage would be that I avoid running a new cable along the outside of the house.

Thanks in anticipation!

The bit I dont like about this is 'poking a crimp into the wall'.......sounds a bodge to me....Cant you fit a small IP rated box over the original light position and leave accessible connections?

 

[Kem]

The bit I dont like about this is 'poking a crimp into the wall'.......sounds a bodge to me....Cant you fit a small IP rated box over the original light position and leave accessible connections?

This

Plus I always fit double pole light switches for outside lights. If a earth neutral fault develops it will constantly trip the RCD. This way if there is a fault you just leave the light switch off.

 

[Ponty Massive]

I've got a customer who wants an outside light removing and a replacement installing about 4 metres away on the same wall. The location where she wants the new light happens to be directly behind the relevant lightswitch.

Is it acceptable to do the following?:

1. Remove existing light.
2. Crimp the N to the S/L at the existing light and poke it back through the wall. This will mean that, at the lightswitch, the wires which were previously L and S/L are now permanent L and N.
3. Now that I have a permanent L and N at the lightswitch, connect a short length of wire and run it through the wall behind the lightswitch to give me power for the new light, with another short length back through the wall to give me a new L and S/L.

Obviously I would only do this if the cable tested out ok, and if I could leave it in such a way that it complied with the regs (in safe zones, etc).

The advantage would be that I avoid running a new cable along the outside of the house.

Thanks in anticipation!

Welcome to the forum..

 

[sparkol]

Welcome to the forum..

Thanks. This forum is ace.

Incidentally, the lighting circuit isn't currently RCD protected. I won't be installing any concealed wiring that would require RCD protection under the regs. However there is of course concealed wiring <50mm deep elsewhere on the circuit.

As I understand it, I don't need to install an RCD. i.e. I don't need to bring the whole circuit up to the regs, only the bit I'm modifying. I'm just planning to note on the MWC that there is no RCD protection and recommend to the customer that she upgrades her CU.

Is that everyone else's understanding? I know its sometimes a point of contention.

Wirepuller - yes I'll think I'll use a little jb - thanks

 

[Deleted member 9648]

This

Plus I always fit double pole light switches for outside lights. If a earth neutral fault develops it will constantly trip the RCD. This way if there is a fault you just leave the light switch off.

Same applies to everything though....why just pick on an outside light?

 

[Kem]

Same applies to everything though....why just pick on an outside light?

Outside lights are more prone to moisture ingress. If you get any moisture in there E+N it will constantly take out the rcd. How often do you get water ingress inside?

 

[SYKRAPS]

If you are DPing the switch as noted above why don't you fit an RCD FCU?

 

[UNG]

This

Plus I always fit double pole light switches for outside lights. If a earth neutral fault develops it will constantly trip the RCD. This way if there is a fault you just leave the light switch off.

Been doing this for a while it's a pain getting a call at an inconvenient time because an RCD is tripping because of a minor problem with an outside fitting

 

[nickblake]

Same applies to everything though....why just pick on an outside light?

well this could happen

 

[Kem]

well this could happen

Let me guess up and down light with 2 x gu10s and no one used sealant to seal the cable entry?