New light fitting in an old house

[Stekahedron]

Hi I'm trying to wire a bathroom light fitting and I have a problem, I have a domino on the fitting with 3 wires blue, brown and yellow/green the wiring coming out of the ceiling where the rose used to be us loop system with two black (with grey insulation) and a red wire and a red wire with a green sleeve (4 in total). I've read my DIY book and google a few times but I think I'm having trouble understanding the process. If anyone could help I'd be great full.
Kind regards
Rich

 

[pjcomp]

I would EXPECT it to be blue to the two black, brown to the red, and yellow/green to the red with green sleeving but I would also test them first - it's a bit unusual to see a red used an an earth (hence the green sleeving) so not to be trusted. Did you note which terminals the loop wires were in? Which terminals was the old pendant wired into in the rose? Such things would help with the diagnosis.

PJ

 

[Stekahedron]

Luckily the first black wire (looking left to right) was
loop (black) line (black) red (neutral) green sleeve (earth)

 

[Stekahedron]

Out of interest and for safety's sake what's the possible outcome of wiring it up incorrectly?

 

[pjcomp]

A loud bang, puffs of smoke, things like that. Don't like the sound of how it was wired in the first place. Get in someone who can test what the wires are doing rather than trying yourself.

PJ

 

[Stekahedron]

Thanks for the advice PJ. I've put the old ceiling rose and light fitting back, the light is working but I've another problem. The two bedroom lights are failing to switch on now, the landing and bathroom work, but now these don't. Any ideas?

 

[EFLImpudence]

Out of interest and for safety's sake what's the possible outcome of wiring it up incorrectly?

A loud bang, puffs of smoke, things like that.

Or the lights in other rooms may not work.


Check the terminations of the Live loop and Neutrals.

 

[1028741]

Usually, there's one red (live SUPPLY), one red that goes from here to the next light, one black (neutral SUPPLY), one black that goes from here to the next light, and a red and black which go to the switch, so three sets of two (T&E) cables in total.
How have you wired up the 4 cables in the rose? You might need to get up in the loft and trace the cables. By the way, you shouldn't be installing light fixtures in the bathroom as it's 'notifiable' work to building control/requires an electrician to sign off the work-I'm worried, because you're having trouble as it is.

 

[securespark]

Pictures will help us a great deal!