I went round to a friend of my mums today to swap two light fittings. They
were both standard type modern metal fittings. His fuse box is one of the
old type rewireable ones with 4 carriers in it, two Red spotted, one white
spotted and one with masking tape over it so not sure of its colour. Now
for safety sake I always turn the light on and then pull the fuse to make
sure it is dead. I flicked the switch and the light didn't come on. He
said "Oh it's because the dining room light is on"!! Apparantly it has been
like that since they bought the house in 1987, if you switch the dining room
light on the living room. kitchen, hall and landing go off!! He said they
are now used to it and it isn't a 'problem' anymore. He said he had the
electricity board around when they first moved in and they said it was safe
but not conventional!

Now the really wierd bit, when pulling the fuses I tried the one with
masking tape first, nothing, then the white one, nothing, then one red one,
nothing, final red one light went out along with
theTV,video,fridge,kettle,cooker, etc. Everything in the house downstairs
and all their lights seemed to go through this one red 30 Amp fuse apart
from the immersion heater which was was on the white one. The upstairs
sockets were fed by the other red fuse.

Needless to say I didn't change the fittings and advised him to get a sparky
in, I know my limits!!

Cheers

John