Hi all. So my missus wants the living room decorating using brushed steel screwless switches. 2 way switching for the main light but none of my lights in my house are earthed. I swopped the switches for the new ones and all worked normally except one of the faceplates felt a bit "strange". On investigation it turns out that it carried a low voltage. The cable from switch to switch is 3 core + E and it turns out that the earth wire was providing the voltage to the faceplate even though it is not connected anywhere. How might this be possible? Any ideas please?
Earth issue
- Thread starter kevb1
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"It Just Is"
This is an induced voltage from the other cores.
You should not be fitting metal plates if you have no earth as should it fault then the plates will have 230v on them which is a bit more than a tingle.
What you have to remember is that electricity can kill a healthy adult in less than a second, so it is a requirement to ensure that your system has the necessary safety features built in, starting with an earth and correct disconnection times.
You should not be fitting metal plates if you have no earth as should it fault then the plates will have 230v on them which is a bit more than a tingle.
What you have to remember is that electricity can kill a healthy adult in less than a second, so it is a requirement to ensure that your system has the necessary safety features built in, starting with an earth and correct disconnection times.
If your wiring is so old that it doesn't have earths to the lighting circuits you would be wise to have it checked out for overall condition before decorating.
It may be OK for continued use but does mean that you can't have any metal switch plates or light fittings.
It may be OK for continued use but does mean that you can't have any metal switch plates or light fittings.
Thx Geoff. I'm intrigued by the fact that the three cables are working perfectly but the errant earth was connected to the back box therefore to the faceplate. The other end at the other switch is not connected to anything. Even back in the sixties when the house was built that would still be an odd phenomena.
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Nothing odd about induced voltages..
its just a law of physics that alternating currents produce magnetic fields..
and cables passing through magnetic fields will have electricity induced into them...
If you have an electric toothbrush, think how does that charge up with no cables connected to the brush body itself?
The more common and strange phenomena, is when people replace electrical accessories without reading the manufactures instructions..
with wording such as "This item must be connected to electrical earth". Yet they fit all sorts of decorative lights, switches, sockets etc..
with un-earthed exposed conductive parts?
If your wiring is that old it would probably benefit from a periodic inspection to double check you have no other potential dangers lurking there..
Excluding double insulated accessories, wiring regulations have required all other exposed conductive parts to be correctly earthed for many many years now.
:coffee
