Are these wires reversed? (ceiling lamp)

[Frostybite]

Are these wires reversed from traditional guidance? It's a very old light fitting in my loft being fed by a switch wire in the loft and the other from the circuit.

I'd expect to see the red wires creating the loop?

I want to replace it with a pendant so I can spur another light off the same switch. But looking at it, it seems the red wires are being used for the switch line and 'in' neutral. Am I seeing that right? Do I continue to use this 'wrong' way round in the pendant?!

The spur s going into a batten holder which I believe means the blue/brown wires can go any way round?

Thanks in advance!

 

[winston1]

Looks like it. Easy enough to test even with a neon screwdriver.

 

[bernardgreen]

If either of those Red wires is Live from from the consumer unit ( fuse box ) then you have the hazardous situation that the lamp holder is always Live even if the switch is OFF. The hazard is the possibility of an electric shock when changing the lamp bulb.

This is the correct way to wire that lamp.

 

[bernardgreen]

Also the Earth wires ( the bare copper wires that have been cut short ) in the two cables need to be connected together and sleeved with green yellow sleeving

 

[ericmark]

Easy enough to test even with a neon screwdriver.

Really good idea, at last some one else who realises neon screwdrivers have a use, I am lucky enough to have a non contact voltage tester I love it, so easy to use, although at £35 not the cheapest non contact voltage tester. But the 4 stage display makes it easy to see which wire is line and which is neutral even if one bar shown on the neutral.

The neon screwdriver has saved me in the past with shared neutrals. Today the clamp on shown can detect that before a cable is removed. But full marks on the neon screwdriver advice.

 

[RandomGrinch]

It's a very old light fitting in my loft being fed by a switch wire in the loft and the other from the circuit.

Do you have relatively easy access to the connections? If so, it may be worth removing the existing wiring completely, starting again with new and doing things properly.

 

[Frostybite]

Do you have relatively easy access to the connections? If so, it may be worth removing the existing wiring completely, starting again with new and doing things properly.

The switch wire yes, the circuit wire no... it comes from under boarding which has central heating piping handily over the top!

 

[bernardgreen]

at last some one else who realises neon screwdrivers have a use

They have a use provided the user is aware of those circumstances where they can give a false reading.

In the OP's case with the Live wired to the lamp the potential on the "reference" ( the hand holding the neon screwdriver ) may be pulled by capacitive coupling towards Live potential. If the reference potential is close to Live potential then the neon may not light when testing a wire that is Live. That could result is the person starting to work on a wire that is Live.

 

[ericmark]

If the reference potential is close to Live potential then the neon may not light when testing a wire that is Live.

But if the person is at line potential, still no shock. But as you say neutral wire would show up as line.

But in the real world, how likely is that to happen?

 

[bernardgreen]

But if the person is at line potential, still no shock.

provided the person doesn't touch anything after testing the wire

But in the real world, how likely is that to happen?

Once could be enough.

 

[sparkwright]

I see this a lot on older wiring.