Having Problems wiring 3 Gang and one 2 way switch

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Hi everybody,

Im new to this Forum in terms of posting but i have been browsing this fantastic site for months for handy DIY tips, I now have a problem,let me explain,

At my sister house i decided to change a 3 Gang switch, Should have been simple BUT, i got lost with the wires and where they go, Her house has the old fashioned wiring system, i now have 4 cables and dont know where they go, :cry:

cable 1, Blk+red
cable 2, Blk+red
cable 3, Blk +red
cable 4, Blk+red

what i do know is there were 3 switches,
1 switch for the downstairs hallway light (controlled only by this switch)
1 switch for the outside exterior light (controlled only by this switch)
1 switch for the 2 way for upstairs landing

From all the 4 cables only 1 Black wire has got some live (as tested with tester) and all the others are dead,
this is what was left of the old switch when i removed the cables..NOTE: THE RED WIRES YOU SEE ARE LOOPED OVER FROM ONE GANG TO THE OTHER.
Image012.jpg

and this is my new switch
Image014.jpg

can someone pls help me,
Also how do i fianlly wire the upstairs 2 way switch with the old fashion wiring using only the Blk+Red wires?
Im not clued up on electrics at all and all i have learnt is from this site,but now i have made a mess with something that i shouldnt have attemted in the first place..Many thanks in advance..
 
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There should be at least 3 wires connected to a 2-way switch.

Were all 12 conductors connected to this switch/box?
 
Could you describe how the upstairs switch is wired. It could be useful to know if there is more than one conductor in any of the terminals.

Does your tester also do continuity as this would help find which wire(s) go to the upstairs switch (by altering the state of the upstairs switch and finding out which conductors downstairs go short curcuit / open circuit)
 
There should be at least 3 wires connected to a 2-way switch.

Were all 12 conductors connected to this switch/box?
i think 1 blk wire was not connected, thats all, all others were connected,that makes 7 wires connected, the cables have only black+reds and not 3 wires..Its the old fashion wiring as they call it on here, but the 2 way for upstairs was working fine..
where shall i Start from since only 1 blk has got some electric..
 
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Next crucial question....

Were any of the blacks NOT connected to the switch but to each other???
 
Could you describe how the upstairs switch is wired. It could be useful to know if there is more than one conductor in any of the terminals.

Does your tester also do continuity as this would help find which wire(s) go to the upstairs switch (by altering the state of the upstairs switch and finding out which conductors downstairs go short curcuit / open circuit)
the upstairs switch has only 2 cables coming to it,(1 from light and 1 from downstairs) both reds from both cables were connected and only 1 blk,the other blk was not connected to anything..Thanks for quick responses..
 
Those are neutrals. (They could, at a pinch, be switchwires, but I doubt it)

You need a multimeter, as mikey suggests.

You need to ID the supply into the switch. This (hopefully) is one of the cables.


Make all the wires safe by putting the bared ends into choc blocks. Next, switch the power back on & teast using the multimeter the reds /blacks together. You should get a reading of between 216 and 252V across a red and black.

They may not be in the same sheath, though.
 
Il invest in a decent multimeter this evening, and il post the results tonight,do i test every blk against every red until i get the readings as above?
 
I think I've got it.

One of the cables with two wires is Live/Neutral In to the box. This needs determining by testing, as I mentioned before.

This live loops across all the commons to feed the switches.

The black of this feed cable is neutral & connects to the neutral of the outside light (which will be the black of the one of the other two wire cables (Again, you need to test which one this is).

The red of the outside light cable goes to the L1 of whichever rocker is nearest to that light fitting.

The cable using only the red and not the black will be the switchwire for the hall. Put this (usually) on the L1 of the middle switch.

The other pair must be the strappers that go to the upstairs position. These go to L1 & L2 of the remaining group of switch terminals.

BUT, PLEASE TEST FIRST TO MAKE SURE MY THEORY IS CORRECT!
 
Thanks so much... Il definately test first..now not knowing which wire is for which light il have to do it your way, step by step. Firstly il find the feed by using meter,( where do i connect this?) im sorry if im causing too much trouble for yourselves, you may tell me to go get an electrician if you want.
 
Il invest in a decent multimeter this evening, and il post the results tonight,do i test every blk against every red until i get the readings as above?

Yes. You must switch off before putting the conductors in their choc blocks.

Only work live when testing!

Make sure you keep fingers well away. Wear gloves if possible.

Take lamps out of all fittings to ensure no neutral feedback through the switchwires.

To test the outside light, set the multimeter to continuity & put one probe to the live terminal in the outside light and the other to one of the reds in the hall switch box.

You'll need to extend the probe with some flex.

Alternatively, put a GLS lamp into the outside light fitting & test with the meter on continuity across a red/black pair in the hall switch box.

You should have continuity when the lamp is in but not when it is removed.

Use the same continuity setting to find the strappers pair.

Remove the strappers (L1 & L2) from the landing switch & join together.

Now use the meter (set to continuity) and test across red/black at the hall switch box. You should have continuity when the pair are joined at the landing position, but not when the connection at the landing switch is broken.

This way you should be able to identify all conductors.
 
Securespark your'e a LifeSaver... you realy know your stuff..
I detected all the conductors with multimeter, The power feed is coming from the downstairs hall light, I managed to turn on the hall and outside lights, Now how do i activate the 2 way for the upstairs from this switch as i only have 2 core (Red+Blk) and earth, it should be possible because it was working fine before,
Upstairs i have 2 Cables coming to switch, 1 obviously for the light and 1 for downstairs (strippers as you called them), Both are 2 core + earth.. Is 2 way switching possible with these cables as Normally they use 3 Core+earth.. Pls advise.. Your help is much appreciated..
 
azztdi said:
Upstairs i have 2 Cables coming to switch, 1 obviously for the light and 1 for downstairs (strippers as you called them), Both are 2 core + earth.. Is 2 way switching possible with these cables as Normally they use 3 Core+earth.. Pls advise.. Your help is much appreciated..

Securespark has done the donkey work already but here goes anyway ---

Your last two-core cable downstairs should be one at the upstairs switch that has both cores connected. You can confirm this with your meter if you put a short across them upstairs (power off of course). In the third downstairs switch you put these two cores into L1 and L2 and link COM across to the incoming live feeds on the other two switches.

In the new upstairs switch you put the two cores of that cable into L1 and L2 just like you did downstairs. The third core, which you should find connects to the light fitting, goes into COM. This is the old-fashioned way of wiring two-way light switches. It does work. :) :) :)
 
Space cat";p="941876 said:
azztdi said:
Upstairs i have 2 Cables coming to switch, 1 obviously for the light and 1 for downstairs (strippers as you called them), Both are 2 core + earth.. Is 2 way switching possible with these cables as Normally they use 3 Core+earth.. Pls advise.. Your help is much appreciated..



The third core, which you should find connects to the light fitting, goes into COM. quote]

Will this be the Red or Blk?
I was looking at the following diagram from this site..
1and2waygc6.jpg


Since the Com downstairs has a live feed will the upstairs com have the live feed too or blk? Or can i switch the wiring around, i.e to use the live feed from upstairs and connect downstairs Com to negative? ( i think thats the way it was done before,There was a black wire in upstairs switch into a choc block Not connected to anything..
 

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