Ligh...ting circuit- problem Ask questions and find answers to many subjects relating to electrics and electrical work

[aidansdad]

Hi There

I have recently tried to relocate a light upstairs in the hallway, simple I would have though just take the wires out the old light fitting(switched off at mains) pop them into a block connector as they were add new wire and attach back to light at desired area..... hmm well no as the light goes on but wont go off at the switch now so i have disconnected the wires and left them just now and it has knocked out the lights upstairs but the lights downstairs work and they are on the same circuit breaker. It is a 2 switch socket upstair but also controlled by a 3 switch downstair..... I am hoping a relative who is a sparky will come round soon but wanted to see if could get fixed

[ericmark]

The light will have four connections

1) Supply Line, likely all the red wires in old system these will need connecting together but do not need to go to new location.

2) Earth wires likely bare with green and yellow sleeves these will need connecting together and also one taken to new lamp.

Now where likely the problem lies the black wires.

3) The switched line likely black and should have a red sleeve but often that is missing this goes to new lamp line connection.

4) Neutrals also black and these go to neutral connection.

Notes:- The latter system uses brown instead of red and blue instead of black. The most important thing is to note the switched line and ensure this does not get mixed up with neutrals as likely same colour.

Since neutral is considered a live wire we use the word "Line" to talk about the phase conductor. L on any appliance stands for Line not Live.

You will find this all under "Projects": https://www.diydoctor.org.uk/projects.htm

[aidansdad]

I followed your instructions and now can get the lights back upstairs but the light I am trying to wire through the block connector and extension cable is going on the same time as the bathroom light now and off too on the one switch as not seperate as before... and not high powered enough now so not very bright.. could this be to do with the extension cable, also

[ericmark]

Sounds as if a neutral and a switched line wire have got mixed up. In the past I have tried to instruct how to find which two black wires have been swapped but it has been a failure.

The only real way is to ring out the wires to find which is which. No real short cuts. At least which are likely to be followed by non electricians.