Lounge light neutral problem

[Martin606]

Lounge lights not working.
No RCD tripping.
No MCB tripping.
Lights wired power-switch-light. New switch and pendant installed.
Meggar test shows following voltages when switch is off.
L-N 235V
L-E 235V
N-E 18V

When light is switched on,
L-N 235V
L-E 235V
N-E 175V

Is someone able to give some advice as to why I may be getting these readings. Continuity and polarity tests fine.
Lights still not working.
Thanks in advance.

 

[HandySparks]

...Continuity and polarity tests fine....

What are your actual R1, Rn and R2 readings at the light with the switch closed? (or R1+R2 and R1+Rn)

 

[telectrix]

sounds like a floating neutral, poor connection.

 

[Pete999]

What are your actual R1, Rn and R2 readings at the light with the switch closed? (or R1+R2 and R1+Rn)

Dont think the OP is a Spark HS

 

[Octopus]

Dont think the OP is a Spark HS

Not sure I agree with that, the op states continuity and polarity good

Edit : having read a couple of previous threads I don’t think he is, nor does he appreciate and questions about ability .......he just expects answers on a plate

 

[Pete999]

Not sure I agree with that, the op states continuity and polarity good

Edit : having read a couple of previous threads I don’t think he is, nor does he appreciate and questions about ability .......he just expects answers on a plate

Glad you agree with me.

 

[davesparks]

Meggar test shows following voltages when switch is off.
L-N 235V
L-E 235V
N-E 18V

When light is switched on,
L-N 235V
L-E 235V
N-E 175V

‘Megger test’ is the common term for an insulation resistance test, but your test results imply that you’ve measured the voltage. Can you clarify what you mean here?

 

[SJD]

Have the lights stopped working after the new switch and pendant were installed? Or were these installed due to the fault, in the hope they might fix it?

 

[gnuuser]

more info is needed here, what location are you testing from?
what is the total length of the circuit from the ring or radial to the lamp?
the original post lends a lot of questions on the qualifications hence the reason for asking if the OP is a spark

 

[GeorgeCooke]

what is the total length of the circuit from the ring or radial to the lamp?

Lights are not wired on rings.

 

[telectrix]

Lights are not wired on rings.

correct. they're mainly wired on the ceiling . .

 

[dksanders]

He can't be a spark as he'd know that with the switch off, L-N would be 0V not 235V.

With the switch on N-E is giving 175V. I've had similar in the past where the N was an unsleeved L and the client in replacing the pendant had got everything mixed up so when the switch was on the switched L was going through this light and the next light in series.

He needs a professional with test gear and more importantly knowledge to get it sorted out safely.

 

[Adam W]

Have you tried changing the bulb?