# Why is my lighting circuit at 20V?

#### alias51

I have just started to learn to use a 2-prong voltmeter. I've been testing the lighting pendants I have around the house, and one is at 20V, whereas the others are at 240V.

Is this usual / is there a reason this is happening?

The 20V doesn't really exist, it's capacitive coupling from adjacent wires.

Could be a extra low voltage light fed through a transformer hidden in the ceiling.

@flameport, thanks. The light circuit is on though, and the lamp works - could this be Capacitive Coupling? Why am i not reading 240V (other than possibly using the voltmeter wrong!)?

@flameport, thanks. The light circuit is on though, and the lamp works - could this be Capacitive Coupling? Why am i not reading 240V (other than possibly using the voltmeter wrong!)?
That's what flameport said it was in his reply!

I have just started to learn to use a 2-prong voltmeter. I've been testing the lighting pendants I have around the house, and one is at 20V, whereas the others are at 240V.

Is this usual / is there a reason this is happening?

20V with respect to what? Which two points are you measuring between?

If your testing between live and Earth, you may have a bad earth. Assuming live and netural is fine of course.

I wonder how you are measuring with my lights to get a meter probes into the bulb holder without the risk of slipping and causing a short circuit would be hard. Even with a GS38 lead set.

Most cheap meters are not supplied with leads suitable for use with 230 volt. The meter maybe OK but the leads are not, GS38 leads can cost more than the meter.

You may be reading between earth and a live and the earth could be missing, you could have a 12 volt lamp and the meter does not like the high frequency so giving wrong reading. But sticking probes in holes without knowing what you are doing can be very dangerous.

I wonder how you are measuring with my lights to get a meter probes into the bulb holder without the risk of slipping and causing a short circuit would be hard. Even with a GS38 lead set.
I've NEVER tried to stick my probes into a pendant lamp holder. Just test at the rose. Pretty sure that's what the OP is doing.

Don't you have a set of Lightmates?! The bayonet pins have fallen off of the BC one on mine, bloody expensive rubbish.

I wonder how you are measuring with my lights to get a meter probes into the bulb holder without the risk of slipping and causing a short circuit would be hard. Even with a GS38 lead set.
I've NEVER tried to stick my probes into a pendant lamp holder. Just test at the rose. Pretty sure that's what the OP is doing.
Possibly in which case he has 4 connectors to select from wonder which he used?

Don't you have a set of Lightmates?! The bayonet pins have fallen off of the BC one on mine, bloody expensive rubbish.
I did have one of these
connected to a 13A socket with a croc clip on the earth so I could easy test with loop impedance tester but some one stole it and no Woolworths any more to get replacement.

Possibly in which case he has 4 connectors to select from wonder which he used?
To get 20V I would have thought switched live (off) to E or N

Don't you have a set of Lightmates?! The bayonet pins have fallen off of the BC one on mine, bloody expensive rubbish.
No, because like you point out, they're bloody expensive rubbish! I have made one myself for Hager Click Roses with some 30A connector blocks and a spare end, but for BC and ES pendants, I just drop the cover. No big deal

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