Lighting fault query

[Welsh_sparky_21]

Was fitting 2 lights today that had been taken down by someone start of the year so the ceiling could be painted. Cables at light switch were marked L and SW so straight away I was thinking that’s no right. Thought id double check I was getting a neutral at light, was getting 24V between live and sw at light (neutral). Opened the switch and the cables were disconnected, but the one marked common was dead, checked all the fuses in the lighting board and all of the cables going away were live. Any ideas other than possible break in cable at some point baring in mind it’s VIRs, was late in the day and have to go back to it. Not the most experienced at fault finding but so just looking for a bit of advice

 

[buzzlightyear]

Any ideas other than possible break in cable at some point baring in mind it’s VIRs, was late in the day and have to go back to it. Not the most experienced at fault finding but so just looking for a bit of advice

I would not have touched it with a long
Barge pole, OK some peaple on here might say has long it passes the IR testing, so no earth there L-N so what was the fitting 1or 2.

 

[ImpededLoop]

Difficult to say without seeing it. However, if it's wired in VIR I'd be wary of the general condition of the wiring. Is it wired in conduit?

 

[Welsh_sparky_21]

Difficult to say without seeing it. However, if it's wired in VIR I'd be wary of the general condition of the wiring. Is it wired in conduit?

Was wired in conduit, all lights working in house bar that switch, I said to the customer the wiring is 50/60 years old so could potentially be broken, told them definitely needs rewired

 

[timhoward]

Cables at light switch were marked L and SW so straight away I was thinking that’s no right.

Am I missing your point as I would take that to mean Live (live all the time) and Switched Live (going to light)

Thought id double check I was getting a neutral at light, was getting 24V between live and sw at light (neutral

That could be induced voltage on the 'floating' switch wire

Any ideas other than possible break in cable at some point baring in mind it’s VIRs

VIR - all bets are now off I'm afraid.
Do you have a permanent live at the fitting?
Some photos would help, but I'd be very very wary of re-energising VIR.

 

[buzzlightyear]

VIR - all bets are now off I'm afraid.

The horse has bolted and trotting down the street , the only way to see is a test end to end.

 

[Welsh_sparky_21]

Am I missing your point as I would take that to mean Live (live all the time) and Switched Live (going to light)

That could be induced voltage on the 'floating' switch wire

VIR - all bets are now off I'm afraid.
Do you have a permanent live at the fitting?
Some photos would help, but I'd be very very wary of re-energising VIR.

So basically 2 cables at the light were in block, one marked L and one marked SW. so straight away I was thinking why is that SW and not Neutral, so checked to see if I was getting a neutral at light. Turned on switch and nothin happened at the light, opened up the switch and the cables weren’t connected. I then tested these cables and was getting 12V at the switch between Live and earth. Was getting 24v between the 2 cables at the light constantly

 

[buzzlightyear]

So basically 2 cables at the light were in block, one marked L and one marked SW. so straight away I was thinking why is that SW and not Neutral, so checked to see if I was getting a neutral at light. Turned on switch and nothin happened at the light, opened up the switch and the cables weren’t connected. I then tested these cables and was getting 12V at the switch between Live and earth. Was getting 24v between the 2 cables at the light constantly

The best way Is get a piece of scrap paper and work out what goes were. So that we can see how it is.