No lights in one room

[Pedge]

Yesterday I was installing some downlights in my living room which I have done twice in the past in other areas of the flat. After checking the wiring was correctly done I plugged the 5amp fuse back into the fusebox where it blew.

I was baffled especially after rechecking everything again and then to rewire the fuse. After rewiring the fuse I plugged it back into the fusebox where the lights now all worked after switching them on. I couldn't understand at the time why the fuse blew.

Later in the evening I went to the bedroom which is on the otherside of the flat and found that the downlights didn't work in there. It seems as if the problem with the fuse blowing may have come from the bedroom which I don't understand. The two other bedrooms, kitchen, bathroom, hall and living room have lighting except for the third bedroom which had been working the previous day.

Today I have changed the lighting switch and connected a normal 60W mains powered bulb which cut out the use of the transformer where the light still won't work. Using a pocket mains tester (screwdriver type that detects current) it seems as if there is no power going to the switch nor to the lights.

Prior to this happening the 5amp fuse did buzz a bit when turning on the lights in that bedroom. The downlights fitted in there where bought from B&Q 4yrs ago which consisted 3lights and one transformer. There was a dimmer connected as well.

I'm not exactly sure if the problem lies with the ceiling rose in that bedroom or somewhere else. Would anybody have any advice before I call out a sparky? I can see it'll probably be expensive as i'll have to cut through the plasterboard to get to the ceiling rose.

TIA

P

[Mark]

Whereabouts and how did you break into the existing circuit with the new set of lights?

Did you put the dimmer in the mains supply or the low voltage one?

[Pedge]

"Mark" wrote in news:dkao57$s4u$ [e-mail]:

I put the dimmer on the mains supply however, it has come to light that I have been not so competant in the last 24hrs. I disconnected the switch in the living room where I was installing the new lights so that I could fit a metal switch surface box to the wall. I then taped up each cable without using the switch and for nobody to use the lights in the living room. Two of these cables were of course leading back to the circuit but I had temporarily ceased each others contact.

I'm assuming one must go back all the way to the bedroom on the otherside of the flat for some bizarre reason. Still don't understand why everything else worked.

Anyway problem now solved and have lights again.

Thanks

[John Rumm]

Sounds like you have the normal "loop in" wiring where the feed runs from one light fitting to the next and a separate wire runs from the fitting to the switch. My guess is that when fitting the new lights you have somehow manged to disconnect (or possibly even short) the feed wire that goes out from them. Hence the new lights work ok and any that follow them won't You will probably find the non working lights are the only set that followed on from the new set).

Which fuse was this? In the CU?

There is normally enough slack in the wires to pull them through far enough to see what is going on. Failing that, fixing a plasterboard ceiling is not that difficult.

[John Rumm]

Ah, are you saying that you have one set of lights in the living room with one switch, but there are two cables at the switch position (i.e. 2 x earth, Neutral and Live)?

If that is the case, then that room at least is not wired with the standard loop in arrangement. A bit of tracing and identifying seems to be in order here!