INSTALLING A DIMMER LIGHT SWITCH - EXTRA WIRES?

[DEJ]

I want to replace the single switch in my lounge with a dimmer. if i copy the way the original switch was wired it will not work.

i have two thick grey wires to work with - one with 2 red and 1 black wires, and the other 2 black one red. The earth wire is screwed into the switch housing.

Out of the two dimmers in B&Q It was a main dimmer switch i was advised to buy - it has 3 holes at the top which are L1 L2 and ~ , the existing switch has two holes at the top and one at the bottom, one red wire is in the top left hole, one red wire is in the hole at the bottom, 3 black wires are all screwed together in a plastic bit completely seperate from the light switch.

Any ideas?

 

[electronicsuk]

Use L1 and ~ connections on the new switch, ignore L2 if there were only ever two connections used on the old switch. I also suspect there may be three grey wires entering the switch, not two as you describe.

 

[DEJ]

There are definitely only two grey wires containing the red/black combination as described. Its baffled me completely. especially how the black wires are connected only to themselves inside a little bit of plastic but nothing else!

 

[RF Lighting]

You didn't try connecting them to the dimmer did you?

 

[333rocky333]

Its baffled me completely. especially how the black wires are connected only to themselves inside a little bit of plastic but nothing else!

They are the Neutral wires.

 

[1john]

you wiring has been looped in and out of the switches instead of the light fitting, dont worry about the black wires in a connector block. Connect as described above and you will be away.

 

[DEJ]

No, i didnt connect the black wires to the dimmer, i just wired it in exactly the same way as the existing one was done (using L1 and the ~).

could a faulty switch be to blame?

 

[Steve]

What is the dimmer switch trying to power? What type of light, and what wattage and type of lamps?

 

[DEJ]

http://www.argos.co.uk/static/Product/partNumber/4323312/Trail/searchtext>ALDER.htm

 

[Steve]

60 watts of 12 volt lamps.

Does the dimmer instructions say "do not use with wirewound transformers" or otherwise make mention of extra low voltage lighting?

 

[DEJ]

No. There is no mention of incompatibilty, only reference to it may not fitting into a 4 lug box.

the dimmer is a 400w 2 way mains voltage switch, bought as recommended by someone in B&Q when i asked which one i needed.

 

[333rocky333]

Your dimmer instructions, does it mention inductive or resistive loads on it.

 

[JohnnyG]

Is it possible that that fitting comes supplied with a non-dimmable transformer?

 

[Steve]

as recommended by someone in B&Q

Never ever ask a member of B&Q staff what you need.

 

[DEJ]

No, nothing about that either! I am starting to think these are very poor instructions!!!

if its any help the dimmer is made by crabtree and the back says:

CPU-2W400
60-400w
200-240v

EN60669-2-1

400w max