Replacing light switch with dimmer

Deanicus

Hi,

Just looking for some advice. I want to replace a standard 1 way light switch with a dimmer. When I took off the existing switch I saw that 2 brown (presumably the live) wires were connected to it. In the mounting box the 2 neutral were terminated into a little joiner thing (don't know the name). The earth was just there. In have a pic attached

The dimmer I have has 3 ports c, l1 and l2. Can someone advise on how to wire it up?

Thanks

meercat

Deanicus wrote: »

Hi,

Just looking for some advice. I want to replace a standard 1 way light switch with a dimmer. When I took off the existing switch I saw that 2 brown (presumably the live) wires were connected to it. In the mounting box the 2 neutral were terminated into a little joiner thing (don't know the name). The earth was just there. In have a pic attached

The dimmer I have has 3 ports c, l1 and l2. Can someone advise on how to wire it up?

Thanks

one brown wire into c
other brown wire into c1

meercat

if you are fitting a metal dimmer connect the earth(green/yellow)wire onto the switch plate too

james142

meercat wrote: »

other brown wire into c1

*l1

finnegan101

also make sue you have bulbs that can be used with dimmers.... some energy bulbs cant...

Deanicus

meercat wrote: »

if you are fitting a metal dimmer connect the earth(green/yellow)wire onto the switch plate too

Thanks meercat. I assume you meant l1?

Thing is I tried a few combos (pride made me try without help :-) ) and think that was one of them. Didn't seem to work. Maybe I fried the switch?

meercat

james142 wrote: »

*l1

thanks
L1

meercat

Deanicus wrote: »

Thanks meercat. I assume you meant l1?

Thing is I tried a few combos (pride made me try without help :-) ) and think that was one of them. Didn't seem to work. Maybe I fried the switch?

shouldnt have fried the switch
make sure you have 60 watt bulb in minimum

Deanicus

meercat wrote: »

shouldnt have fried the switch
make sure you have 60 watt bulb in minimum

Its actually a 5 light fixture in the sitting room. Think it has 5 40w bulbs (incandescent) but not sure. Will that not work?

Thanks again for the help

meercat

Deanicus wrote: »

Its actually a 5 light fixture in the sitting room. Think it has 5 40w bulbs (incandescent) but not sure. Will that not work?

Thanks again for the help

yes,thats 200 watt total
assuming you have 250 watt dimmer


there are only 3 different ways you can connect your switch
1 has to be right
c+L1
C+L2
L1+L2

finnegan101

that should be fine...

markad1

The C is your common for switch feed loop in and out to next switch C if another switch is in the circuit after this one.
L1 is the switch wire for your light or if 2 way switching is used this is connected to L1 on the other switch.
L2 connects to L2 on the other switch that's part of the 2 way switching.
Your neutrals are joined in a connector.
Your earth should be used if it's a metal back box or metal switch.
Hope I haven't confused you.
Mark.

Deanicus

Thanks guys. I'll give it a shot tomorrow

Deanicus

markad1 wrote: »

The C is your common for switch feed loop in and out to next switch C if another switch is in the circuit after this one.
L1 is the switch wire for your light or if 2 way switching is used this is connected to L1 on the other switch.
L2 connects to L2 on the other switch that's part of the 2 way switching.
Your neutrals are joined in a connector.
Your earth should be used if it's a metal back box or metal switch.
Hope I haven't confused you.
Mark.

Thanks Mark. Think I understand :-)

Deanicus

Hi guys

Just checked the box and its a "400w 1 gang 2 way dimmer" so I am assuming its fine as it will only be powering 250 watts. Also I assume the 2 way part refers to the L1, L2 bits?

markad1

Deanicus wrote: »

Hi guys

Just checked the box and its a "400w 1 gang 2 way dimmer" so I am assuming its fine as it will only be powering 250 watts. Also I assume the 2 way part refers to the L1, L2 bits?

You want the C and L1
1 gang = 1 switch
2 gang = 2 switches

Deanicus

Hi guys,

I tried all the various combinations and unfortunately it didnt work. I am getting a replacement dimmer tonight in case it was defective.

Before I start again, I just want to double check something with you guys.

I understand the 2 neutral wires are redundant in this setup so I am happy that they are to be left in the connector block. The earth though is confusing me a little.

When I took the original switch off for the first time, the earth was not connected to anything, it was just sitting in the mounting box. My assumption is it should have been connected to the earth terminal in the box?

In any case, the dimmer I got is a brass one and so it needs to be earthed. Can I just connect this loose earth to it? The wiring instructions that came with the dimmer seem to suggest that the earth coming from the wall should be connected to the mounting box and a separate earth wire should be ran from the dimmer to the same earth terminal in the mounting box. Does that sound right?

Thanks again for all your help guys

Cheers

Dean

markad1

If the back box is metal connect the earth to that then loop it to the dimmer switch. All metal parts should be earthed.

Deanicus

markad1 wrote: »

If the back box is metal connect the earth to that then loop it to the dimmer switch. All metal parts should be earthed.

Hi Mark,

The back box is plastic with a little metal piece for the earth in the right bottom corner.

Just so I am 100% (cant be too careful with electricity) I should connect the existing earth to this and then run another earth from the dimmer to this same point?

Thanks

markad1

you can connect your earth directly to the dimmer earth terminal, no need to connect it to the plastic back box.

speedbird184

I bought a 2 gang dimmer switch to replace the light switch in my living room. Nowhere on the dimmer switch is it marked C, L1 L2 etc. The original light switches had a brown and blue wire interconnected, and 1 brown wire by itself. How can I possibly work out which of the 3 points on the dimmer assembly corresponds to the C l1 and l2?

meercat

speedbird184 wrote: »

I bought a 2 gang dimmer switch to replace the light switch in my living room. Nowhere on the dimmer switch is it marked C, L1 L2 etc. The original light switches had a brown and blue wire interconnected, and 1 brown wire by itself. How can I possibly work out which of the 3 points on the dimmer assembly corresponds to the C l1 and l2?

Look closely. It should be there imprinted into the dimmer near the connection screws. Have yet to fit a dimmer that had no markings.