help with tripping fcu from ring mains

17 Jun 2008
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United Kingdom
help, i have recently connected a 13amp switched fcu (using 5 amp fuse) from the ring main double socket to feed to bedroom wall lights that have separate switches.

i believe i have wired eveything correctly, 2.5mm wire from socket to fcu and 1.5mm from fcu to switch then on to wall light. there are 2 wall lights and both run separatley into fcu, via there own separate switches.

when i switch on the power at the cu and turn on the fcu the power trips off ?

i have tried different fuse size and the same happens.

the switches for each light are 2 way, but are wired as if one way, could this be the problem ?

any help appreciated.

Light Light
| |
| |
switch switch
| |______________
|______________________ FCU ---- doubl socket (ring main)
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At a guess ..have you taken 1.5 to the switch & connected both blue & red to the switch terminals?
If so you are putting a dead short between line & neutral.

Post some pictures up of the connections you have made at all terminals.
forky said:
1.5mm from fcu to switch then on to wall light

Comms beat me to it. Putting the light in parallel with the switch is a classic boo boo. If you did it right you would have needed a piece of choc block (or similar) inside each switch to join the neutrals together. Live from the FCU goes to one side of the switch and switched live to the light comes out of the other side. How are yours wired? :?: :?: :?:
Either that, or you've whacked a nail through a cable fixing the capping?
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Or maybe you trapped a live wire under a switch plate fixing screw and crushed it against the back box - like I once did! :oops: :oops: :oops:
cheers for your help.

i had connected the neutral to the switch terminals, i have now connected the blues and bypassed the switch.

all working safely.

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