1 way light circuit query

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diy_dave1978

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Hi,
A family member has a switch in a bedroom. The house was recently rewired and passed the tests etc.etc. I'm not claiming it is incorrect, but merely trying to improve my understanding. (Out of curiosity more than anything else).

Neutrals are typically "in the switch" for this house.

The follwing image appears to be the circuit including a 1 gang, 2 way switch. Three twin and earth cables go into the switch. It controls a single light. I expected to see the neutal wires joined together. However, they are not in their own connector block/wago. The earths are.


The following diagram is the only way I can guess it is configured. Some of this is from memory. Could it be correct? (CPCs omitted)



SW.png


I could well be way off track :)
 
ericmark said:
I would guess that's what you have, as the diagram would not work.
Click to expand...
It will work with the switch being in a position that the neutral goes from common to L1.

I am sure the OP has misinterpreted it. Never in my life I've seen a switch wired like that.
 
Jurassicspark said:
Never in my life I've seen a switch wired like that.
Click to expand...

You haven't lived

1720111341865.png


This was how a house was wired. It worked because the switches were ancient ceramic ones where the moving contact moved about 10 mm from one fixed contact before coming into contact with the opposite fixed termimal.

The moving contact in a modern switch has much less movement ( circa 3 mm ) and when switching can extend an arc to bridge Live to Neutral

It was found when a ceramic switch was replaced with a modern switch which burnt out in less than a week.
 
bernardgreen said:
This was how a house was wired. It worked because the switches were ancient ceramic ones where the moving contact moved about 10 mm from one fixed contact before coming into contact with the opposite fixed termimal.
Click to expand...
Interesting..
bernardgreen said:
It was found when a ceramic switch was replaced with a modern switch which burnt out in less than a week.
Click to expand...
Which era was it replaced in?
 
Interesting idea, a little unusual.
If the switch contacts break before make it would "work" OK but have the disadvantage of being permanently L at the lamp because it is switching the N not the L.
If it was wired the opposite way round it would work.
Off course if it switches make before break it would blow the switch up with a bang (if fused) or a thwack (if MCB).
 
bernardgreen said:
You haven't lived

View attachment 348030

This was how a house was wired. It worked because the switches were ancient ceramic ones where the moving contact moved about 10 mm from one fixed contact before coming into contact with the opposite fixed termimal.

The moving contact in a modern switch has much less movement ( circa 3 mm ) and when switching can extend an arc to bridge Live to Neutral

It was found when a ceramic switch was replaced with a modern switch which burnt out in less than a week.
Click to expand...
Also known as "The Two Way Hamburger" as I was informed a few years back.

I would not like it but it does work - at the lamp you would have two Ls or two Ns = off or one of each which = on.
 
ebee said:
Also known as "The Two Way Hamburger" as I was informed a few years back.

I would not like it but it does work - at the lamp you would have two Ls or two Ns = off or one of each which = on.
Click to expand...
It‘s known by a number of different names, California three-way is one of them (ambiguous, because apparently that‘s used to describe two different 2-way switching arrangements), in Germany „Hamburg 2-way“. Some German sparks loved it because they could feed a 2-way switch and earthed socket with only three cores back when TN-C was still acceptable.
 
Hi,
Just to conclude the thread, my diagram, as suggested, is nonsense.

The light switch is by Hager and has a loop terminal built in as ericmark suggested. Search "Hager Sollysta" for examples.

Thanks.
 
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