Installing a 3 way dimmer switch… newbie question !!

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Mike.45

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I need to switch my failed 3 phase light switch to a simple 3 way dimmer switch. The markings on the failed switch terminals are N, SL and L…….. But the new dimmer switch terminals are marked L1, L2 and a wave with arrow symbol….. which corresponds to which …!! 💁🏼 Thanks
 
A three phase light?
Can you show the terminals on both switches.
 
I was told that is what it was … 🤷

The white one is the failed switch, the black one is the new dimmer switch…..
 

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Not seen an N terminal on a dimmer switch before. You say it is three way so is the light controlled by more than just this dimmer switch.
 
Yes, two switches, the failed one is a multi programme one re led colour and suchlike, it’s the third one we have had that only lasts 12 months, I just want to put a simple switch into replace it but the three connections confuse me !
 
I have not installed these switches so I really have no knowledge of them. From the wiring I cannot see how it operates as two way hopefully other members may be able to help.
 
Can you post a picture of the terminals at the other switch that controls the lights.

What you have is a switch with a neutral and live feed, and single switched live output, so I'm interested how the second switch controls the lights as that is not a standard 2 way switching set-up
 
I saw something similar the other week I think, are they touch dimmers rather than a knob? I think the sl is slave rather than switch live, and they had touch dimmers at multiple points.
 
A 3 phase dimmer. Takes me back to the old theatre dimmers where you needed a brush handle to dim several at once.

Open coils and copper sliding up and down them. Looked more in place in Dr Frankenstiens lab.
 
As far as I know the light is controlled by single dimmer only.
You can have additional slave units to control master unit (dimmer itself) - like 2/3 way switching. They are often battery powered and use RF to communicate with each other (eg. check Retrotouch dimmers) or via wire.
There are also have all sorts of smart dimmers (Aeotec, Fibaro) or dimming lights like Hue, smart bulbs.
In general, all the smart stuff and touch dimmers need neutral to work; some manage without (passing little current via light even when off) but it can create side effects (light glowing or strobe effect...).

No idea how to wire your dimmer - there should be a manual. I can't see any terminals to slave units in neither old nor new dimmer you have. So if you really have "3 way" dimmers they probably communicate via radio. In that case the new dimmer should be from the same manufacturer and be able to talk to slave units. Unlikely a different brand will work.

This is at least my understanding.
 
I was told that is what it was … 🤷

The white one is the failed switch, the black one is the new dimmer switch…..
Careful with this one. The white fitting has neutral, switched live (SL) and Live(L). The dimmer switch deals with live only. If it is one way (ie only the one switch to the light) then use the common terminal (the wiggly icon) for live and either L1 or L2 for the switched live feed to your fitting. L1 and L2 allow you to connect a parallel switch for 2 way control for which you will probably find a wiring diagram included with the dimmer. NB no neutral to the dimmer switch or sparks will fly. To be clear, the neutral is not switched, it stays at your light fitting.
 
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I think we are getting confused and at cross purposes through terminology here. Mike, Can you please define exactly what you mean by, "three way" .
I think he means 2 way.

I think it is a master/slave situation so he will have to change both switches and run a triple and earth between the two. The new switch will need its earth terminal connected as well.
 

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