Loop circuit problems

[mrreaney]

I wonder whether you can help! I need to rewire a light fitting in to my bathroom. I have a standard cieling rose with a 3-3-2 terminal. However, unlike all the diagrams, I have 4 thick wires coming from the cieling rather than 3. Left to right, these include:
(1) neutral blue, yellow with red tape, red
(2) red, black. One earth casing incorporates wires from 1 & 2.
(3) red, black
(4) red, black with red tape. One earth casing incorporates wires from 3 & 4.

Please could someone explain how I am to wire these to the terminal block. I am stumped!

 

[matty m]

Hi there, if i had to guess, I would say that Cables 2 & 3 are the mains in and mains out, Cable 4 is the switch wire and cable 1 is a supply to an extract fan.

connections :
all reds in the middle three terminals, the switch wire black(4) and the yellow(1) in the 2 live terminals, the 2 blacks cables (2) and (3) and blue cable (1) in the three neutral terminals and all cpc's (earths) in the earth terminals.

this is speculating that there is a fan and the permanant supply to the fan is red and the switched live is the yellow.

obviously the colour of a cable does not neccessarily mean anything if previously wired by someone who doesnt know what they are doing!


hope this helps

 

[ebee]

I suspect you also have extractor fan with timed overrun.
If so then the most likely connections (I say most likely because you never know what someone else has done - so be carefull)

The red, black and earth are loop in from last light and loop out to next.
of the red & black (taped red) the red is phase connect to the afore mentioned reds.
The black (sleeved red) is the switched phase to lamp.
The red, yelow (taped red) & blue is for the fan :-
Red = phase to go with the other three true reds.
yellow (taped red) is switched phase to start the fan.
Blue (should be taped/sleeved black is the nuetral to go with the two loop in blacks to give a neutral connection for both lamp and fan.

Having said all that its easier to draw it than write it.

Take care

 

[Earthling71]

I have the much the same problem.

4 cables of 3 wires, 2x2 cables have the Earth wires coupled (2 wires). The rest of the wires are Reds and Blacks only but not sure which is which
(switch, power feed, extractor, loop).

And yes one of them is for extractor fan. Is there any way of testing the connection and then labelling without doing any damage?

If possible could someone please put this solution into diagramatic form?

Any help would be greatly appreciated.

Many Thanks!

 

[ban-all-sheds]

I have the much the same problem.

4 cables of 3 wires, 2x2 cables have the Earth wires coupled (2 wires). The rest of the wires are Reds and Blacks only but not sure which is which
(switch, power feed, extractor, loop).

You can tell which are the switch and extractor cables by looking to see which terminals they are attached to in the ceiling rose, assuming the fan is controlled by the light switch. If not, then the fan cable will be on the same terminals as the in & out loop..

And yes one of them is for extractor fan. Is there any way of testing the connection and then labelling without doing any damage?

Use your multimeter to identify incoming loop.
If you need to identify the fan cable, it will be the one whose L/N resistance changes when you operate the fan switch...

If possible could someone please put this solution into diagramatic form?

Lighting circuits are in For Reference - you should be able to cope with the concept of a 4th cable for the fan....

 

[Fezzie]

sounds to me like the 2 red black cables are your main loop in loop out,
your red, yellow(taped red) and blue are for your fan on a timer. (live switch live and neutral respectively. and your red and black(taped red) are your switch wires.

 

[ban-all-sheds]

That's what matty & ebee said over a week ago....