Wiring A Kitchen Light

Gaz1234 · Jan 22, 2010

Hi everyone, would be very grateful for some help please. My grandad got his neighbour in to fit a new ceiling rose in his kitchen. The wiring in the house must be a good 25-30 years old (maybe more). When the neighbour took off the ceiling rose, only 3 black wires were visible - 2 wound together an 1 on its own. The red wires were connected to a chocolate block. None of the black wires had a red piece of tape on them so the neighbour assumed that the single black wire was the switch and proceeded to connect it next to the brown (live) wire on the ceiling rose. He then connected the 2 black wires wound together next to the blue (neutral) wire on the ceiling rose. When the mains was switched on, they tripped and the bulb fused/blew!!!!

He then proceeded to swap them over - such that the single black wire was now next to the blue (neutral) and the 2 black wires wound together were next to the brown (live) wire. He switched the mains back on and everything now works fine. The light goes on and there is no tripping of the mains.

Does that mean that he has connected it properly. If the light stays on and there is no tripping of the mains, does that mean everything is okay? On my lighting circuits at home, the 2 black wires are always found next to the blue neutral wire and the single black wire (with red tape) always next to the live. Yet the system tripped when the single black wire of my grandads light was connected to the live. There was no red tape on the single black wire of my grandads light. Does that mean that his system is different because it is old wiring. Is the fact that the single black wire attached next to the blue neutral okay.

I just want to know whether everything is okay. If his neighbour tried it one way and the system tripped, is the wiring now correct now that he swapped the wires over?

Thanks for your help

Gaz

acat · Jan 22, 2010

If nothing is tripping out it may be ok but you cannot take anything for granted without proper testing of the circuit for example the lights may work ok but what about the earthing arrangements have the lighting circuits got earthing cables at all and if so have they been reconnected properly. Lights will work without an earth you only discover the lack of an earth when you get a shock and by then it may be to late.

Best advice is get an electrician in to confirm that everything is where it should be.

Chris

flukey · Jan 22, 2010

sounds very strange to me as the light should work either way round as you only have a switch live and neutral

ghost · Jan 22, 2010

I too would recommend it being checked by a spark, for your piece of mind.

Deleted member 9648 · Jan 22, 2010

You say when he initially switched on the bulb blew,it may be pure coincidence that the bulb happened to blow when he switched on and a blowing bulb does sometimes trip the mcb or even blow a rewirable fuse. Not entirely unlikely as I know from experience that a bulb can work fine for years until it is disturbed when it pops straight away.As already stated which way round the live and neutral are connected should make no difference on a ceiling rose/pendant, so the above senario would seem to me to be the likely explanation.

Gaz1234 · Jan 23, 2010

Hi everyone, thanks for your help. My grandads fuse box has no MCB's. If the supply trips, every electrical appliance and lights in the house turn off. Apparently, when the light blew/didn't switch on the first time and all the power went off, the bloke turned the power back on without the bulb and the system still tripped.

A few of you mentioned that it should work either way round. Does that mean that how it is wired at the moment is okay - i.e. with the 2 black wires wound round each other at the ends next to the brown live wire and the single black wire next to the blue neutral wire?

Thanks

Gaz