No lights working - fusing

[jbason]

I was walking around in the loft today and the lights in the house tripped. I can see that the white 5a fuse had tripped so I tried to move it to the on position but when I did these a spark came from the fuse and all the electric went off. I think it has the RCD that tripped. Moved the RDC back to the on position and everything works again expet the lights. Everytime on try and move the lights fuse back to 'on' it trips the RCD.

I have checked the loft for damaged cables but can not find any, not sure if it was just a coincidence I was in the loft. Any ideas of things I could check? or am I just going to have to get a professional in?

 

[Adam_151]

Its clear that from the behaviour of the protective devices when you try and reset them that you have got a live to earth fault somewhere, now it could be a co-incidence that you were in the loft, but i'd put 50p on it not being so?

Is your loft boarded?, sometimes loft boards are just thrown in and if you get one thats trapping a cable between a joint and itself, eventually it'll damage the cable after being walked over a good few times and go bang

 

[echoes]

I was walking around in the loft today

It sounds like you have a L-E short-circuit.
Did you tread on a junction box? Or maybe disturb a cable that was loose in a ceiling rose or junction box?

Not unheard of to find lives or earths twisted together unenclosed on old lighting circuits either.