Changing a outside light to security light HELP

[thereeces]

Hi i had a outside light that i was going to replace with a security light the problem is i made a school boy error of not remembering the existing wiring! ops my problem is that i have three cables two have got 2 red and 1 earth wires the other has 1 red 1 black and 1 earth the switch that operates the light has 2 red and 1 earth wire.
I have no idea where the cables come from or why there is 2 red wires in the cable any help would be appreciated
Thanks

 

[Steve]

Ok, the red from the R+B cable, connect this to one of the other reds.

Now you have one red and one black.

Connect these to the light.

Voila!

Though how you intend to accomplish this within the confines of a security floodlight is beyond me.

 

[wingcoax]

He still has a twin red to sort out. Have you got a multi meter? Do as Steve says and see what does not work and check with meter if one of extra reds is live.

 

[thereeces]

Hi yes i can get a meter does it matter which cable i connect and what about the switch! which is the switch live?
anymore help
Thanks for the quick responses

 

[wingcoax]

One of the twin reds should be the switch cable, and the red/black should be the supply cable. check with the meter on the red/black and you should have 240vac. Put your meter on continuity and check the twin reds, with the switch on you should get a reading and with it off no reading. The other twin red is an unknown. As said ,see what does not work after.

 

[thereeces]

Many thanks you have all been very helpfull

 

[thereeces]

Hi looks like the twin red is the live cable and not the black and red one as i thought! so i have identified the switch live which is one of the twin reds the black and red seems to go nowhere with the other twin red showing 239 volts so my qestion is how do i identify which is the live and which is the neutral on a twin red cable
any help would be appreciated
thanks

 

[sparkwright]

It seems that the one of the twin reds is live and neutral in,
the other twin red is the switch wire,
and the red and black goes to another light.

To test which is the live on a twin red, test with a voltage tester between a red and the earth.

Obviously the earth wire will have to be connected to earth.
Also, as you are working with live electricity, work safely.
Connect any bare ends in connectors or similar as you work for safety.

The red and black will go to either a light in the house, or to another outside light, so you will have to decide if the live on this cable needs to be connected to switch, or the permanent live block.

If you only had the one outside light on that switch, then the live will go into the permanent live block.

If you are certain one of these reds is in fact a neutral, then sleeve it black.

Work safely.

 

[thereeces]

Thanks for the quick response ive check the twin red which isnt the the live switch and dont get much volts with one red and none with thew other red i presume the one that is showing a little is the live of the twin red??
thanks

 

[thereeces]

All sorted now
Thanks