Need Some Help With A Light Fitting Please.

[Kostya]

Had a bit of a problem fitting a light for my friend. I took a
picture before I started to disconnect the old fitting, it's pictured
below.

So my problem is, I assumed all the blacks
were neutrals and the reds were live and connected up the new fitting
that way. The problem is the fuse blows as soon as it's inserted, I've
tried 3 fuses and they all blew when the main switch was flicked, so I'm
guessing something is shorting out. Have I identified the cables
incorrectly?

Any help would be great, my friend has no
lights upstairs at the moment and I feel like a complete idiot.

 

[Andy™]

chances are, you have blown the switch and its welded shut, so no matter which way you connect the cables, it will always short out

you need to test which cable is the switch, and if its broken or not before going any further

there is also a lack of earths in there

 

[betty swollocks]

Red to red black to black blew to f...... Andys correct one of the cables goes to the switch you need to find which one, have you got any test equipment? Even a multimeter will do

 

[SPECIAL LOCATION]

On your picture the three reds are permanent LIve.

The two blacks on the right are the Neutrals

The single black on the left is the Live from the switch to the light.. (It should have had a red tape or sleeve around it.)

 

[ProDave]

So you took a photo of how it WAS. Then you connected it DIFFERENTLY  (all blacks together) : headbang

and you wonder why it didn't work?

Advice to anyone reading this thread, note how it was and connect it the same. In the case of same colour wires going to different places, label them somehow so the right ones go back to the correct place.

 

[betty swollocks]

The picture shows 3x red lives in the centre labelled loop. 1x black to the left labelled N for neutral. the right hand side has 2x blacks, basically you should have the switch return in the right hand ( as you look at the picture) terminal and two blacks in the N neutral terminal, what you are describing is, when the switch is made the two blacks together a making a dead short and blowing the fuse, you need to find which of these 2x blacks is the switch return and which is actually a neutral, a multimeter will tell you in seconds, what you should end up with is 3x reds in centre 2x blacks in N neutral terminal and 1x black in the right hand side SW terminal.

 

[Kostya]

chances are, you have blown the switch and its welded shut, so no matter which way you connect the cables, it will always short out

you need to test which cable is the switch, and if its broken or not before going any further

there is also a lack of earths in there

Thankyou. Yes the earths are all chopped off, the previous owner did quite a lot of electrical work in the house so my friend says.

Red to red black to black blew to f...... Andys correct one of the cables goes to the switch you need to find which one, have you got any test equipment? Even a multimeter will do

Hi yes, I have both a multimeter and an LED indicator test lead.

On your picture the three reds are permanent LIve.

The two blacks on the right are the Neutrals

The single black on the left is the Live from the switch to the light.. (It should have had a red tape or sleeve around it.)

Thankyou for the reply! The problem I have is the new fitting only has live, neutral and earth connections, where do I connect the switch wire?

So you took a photo of how it WAS. Then you connected it DIFFERENTLY  (all blacks together) : headbang

and you wonder why it didn't work?

Advice to anyone reading this thread, note how it was and connect it the same. In the case of same colour wires going to different places, label them somehow so the right ones go back to the correct place.

Yeah I know, I'm an idiot fella I admit it :Blushing

 

[betty swollocks]

Then test for continuity between pairs of red and black whilst operating the switch, you should find continuity between one pair only, continuity when the switch is made, broken when the switch is off, that is the switch wire, mark that black with tape red / brown and then put that into the SW terminal the other 2 blacks in the neutral and the 3 reds in the centre.......... In a new fitting with just live neutral and earth insert SW into the live 2 blacks in the neutral and the 3 reds into a spare chock block of some kind as they are not required as such

 

[Kostya]

Then test for continuity between pairs of red and black whilst operating the switch, you should find continuity between one pair only, continuity when the switch is made, broken when the switch is off, that is the switch wire, mark that black with tape red / brown and then put that into the SW terminal the other 2 blacks in the neutral and the 3 reds in the centre.......... In a new fitting with just live neutral and earth insert SW into the live 2 blacks in the neutral and the 3 reds into a spare chock block of some kind as they are not required as such

Hi, thanks for your responses (and everybody else's), the light fitting only has a live, an Earth and a neutral block, where do I connect the switch-wire once I locate it?

 

[alpha spark]

Use a connector block for the reds this is known as the loop terminal

 

[betty swollocks]

the light fitting only has a live, an Earth and a neutral block, where do I connect the switch-wire once I locate it?

The black wire which you have proven with your tester to be the switch wire is now the live to your new light fitting, the 3 reds simple get chock blocked together but do not need connecting to your light fitting at all

 

[Kostya]

The black wire which you have proven with your tester to be the switch wire is now the live to your new light fitting, the 3 reds simple get chock blocked together but do not need connecting to your light fitting at all

I get it now! Thankyou so much and thankyou to everyone who responded! This forum is going to come in very handy for me

 

[monkey5]

also make sure you retermate the earths if theyve been cut.

probably my eyes but does the cable look rubbery, so might not have any earths.

 

[Kostya]

also make sure you retermate the earths if theyve been cut.

probably my eyes but does the cable look rubbery, so might not have any earths.

Hi, all three are twin & earth, they have just been cut back for some strange reason. I just hope there is plenty of spare so I can earth up the light as it's made of metal, the cables didn't seem very slack but I'll just have to wail till tomorrow to be sure. Not sure what to do if I can't though. Fingers crossed.

 

[SLIPSHOD & SLAPDASH]

If the earths are cut off there, they may also be cut off at other  lights so don't simply connect and forget but test to check continuity

 

[Kostya]

If the earths are cut off there, they may also be cut off at other  lights so don't simply connect and forget but test to check continuity

I will do that, thankyou. What if there is not enough length to terminate the earth?

 

[SLIPSHOD & SLAPDASH]

Fit them  all into a connector block and use a short link  of cable to go from there to your light fitting

 

[Kostya]

Fit them  all into a connector block and use a short link  of cable to go from there to your light fitting

Appreciated, thanks again

 

[Kostya]

Just want to say a big thanks again for everyone's advice. I sorted the problem quite easily as the wires fell into the position they were once in when disconnected, so identifying the switch-wire was a breeze. My biggest fear was one of the screws I put the fitting up with had penetrated a cable so I'm very happy.

Thankyou!

 

[SLIPSHOD & SLAPDASH]

Thanks for replying