I've decided to add a dimmer switch but when I took off the rocker switch I noticed that there was 3 red live wires, one each going to Com, L1 and L2.
How can this switch work when there's no neutral?
Old lighting cables
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joee2027
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Old lighting cables
Hello All,
I've decided to add a dimmer switch but when I took off the rocker switch I noticed that there was 3 red live wires, one each going to Com, L1 and L2.
How can this switch work when there's no neutral?
I've decided to add a dimmer switch but when I took off the rocker switch I noticed that there was 3 red live wires, one each going to Com, L1 and L2.
How can this switch work when there's no neutral?
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Hoovie
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in leui of one of the pros answering this, the neutral is conencted to the light fitting itself.
The light switch is used to route the live to the fitting - so when you open the switch, there is no live to the fitting.
Common is permentantly live, the other reds (which may actually be other colours with a red sleeve on, are switched lives that go to light fitting.
The light switch is used to route the live to the fitting - so when you open the switch, there is no live to the fitting.
Common is permentantly live, the other reds (which may actually be other colours with a red sleeve on, are switched lives that go to light fitting.
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Rich-Ando
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the only time you may find that isn't true Hoovie is when it's a two-way switch.
in that situation the "C" common can simply be a strapper or a return switched live.
usually in 2-way switching L1 is usually the permanent live but that depends which switch it is and how old the wiring is.
wired in singles is one way & wired with 3-core is another.
in that situation the "C" common can simply be a strapper or a return switched live.
usually in 2-way switching L1 is usually the permanent live but that depends which switch it is and how old the wiring is.
wired in singles is one way & wired with 3-core is another.
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Stoday
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An old way of 2-way switch wiring is to connect one of the two switch's common terminal to permanent live and the other switch's common to the lamp. Two strappers connect the two L1 and L2 terminals. This way you don't need a 3-core cable.
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joee2027
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The house hasn't been rewired in about 25 years. I've looked in the loft and they are some two core cables, one red (live) and one bare, which I presume is the Earth.Stoday wrote:An old way of 2-way switch wiring is to connect one of the two switch's common terminal to permanent live and the other switch's common to the lamp. Two strappers connect the two L1 and L2 terminals. This way you don't need a 3-core cable.