Electric wiring for ceiling light

T

therookiefal

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In my dad family home, built 1979, the light in the porch is falling apart and needs to be replaced.

It is a single light bulb linked to a switch on the wall.

I have taken it down and I can see there are 3 cables going into ceiling/batten light.

None are earth.

Two are going into one connection and one is going into another.

QUESTION - as none of them are marked, I don’t know if the two cables going into the single connection are the live or the neutral.

QUESTION - as I need to replace it I have a modern ceiling rose that has the wiring capacity for running the lights like they are in a circuit/series.
As I am not in a series do I keep the same approach as the old and put the two cable into one connector?
 
Yes keep the two cables in the same connector block.

When you are doing the job switch off the lighting circuit breaker or remove the lighting fuse at the distribution board. Don't just switch off the porch light wall switch.

If you are unsure how to turn off the lighting circuit at the distribution board, turn off the main switch or remove the main fuse.

Put a bit of insulaton tape on the single cable to identify this from the other two.
 
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The 2 wires together are usually the live, permanent live and the switch live. The single wire is usually the neutral. Use a multimeter to test them.

• Find the permanent live (should always have 230 V).

• The switched live becomes live only when switch is ON.

• The neutral has no voltage.
 
FANTANA said:
The 2 wires together are usually the live, permanent live and the switch live. The single wire is usually the neutral.
Click to expand...
In this situation the poster is working at a ceiling rose.

The two connected cables will almost certainly be neutrals.

The single cable is most likely to be the switched live.

All cables should be treated as potentially live.

If a neutral loop is feeding other ceiling lights in the house and if any of these lights are turned on, when the two neutral cables are separated the looped neutral will have a voltage.

If you tip this you will earth this cable and be in series with the other switched on light fittings and get an electric shock.
 
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S class said:
If a neutral loop is feeding other ceiling lights in the house and if any of these lights are turned on, when the two neutral cables are separated the looped neutral will have a voltage.
Click to expand...
I found this out the hard way, the only consolation was the sparks that came to finish the job got a wack too. When he figured it out, it was a downstairs light on the upstairs neutral, so even though I'd isolated the correct lighting circuit once the neutrals were disconnected, one was live!
 
Many years ago when I was doing some light electrical work in a house an electrician gave me a little bit of advise
When changing sockets and light fittings, after you've checked its working and before you finally screw the fitting to the wall/ceiling,
Double check the connectors for tightness as it will surprise you how many will need retightening
 
FANTANA said:
The 2 wires together are usually the live, permanent live and the switch live. The single wire is usually the neutral.
Click to expand...
I'd say the opposite. The permanent live and the switch live will definitely NOT be together. Other wise the light stays ON all the time.
The single cable is likely to be the switch live. The permanent live will be at the switch (On the wall) and not at the light fitting.

The two cables are 'loop in / loop out' neutrals.

I have wired many the lighting circuit.......and many the house for that matter!

Side Note - Professionals do not use phase testers anymore.
 
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