Any electricians on here? Help please.

[Swordfish7]

I am doing a bit of work on my house and have taken down a partition wall in the hall. It housed a double throw light switch for the landing light.
When checking the upstairs switch to find which cable was common I noticed that the earth cable has a current - it makes my neon screwdriver light-up.

I checked the light fitting where it does the same and so used a meter between the neutral and earth which reads 0 volts.

How much voltage is required to light the neon tester?

What could cause this?

Any advice appreciated.

 

[Skip Donoghue]

Never use a neon screw driver to test if something is live or dead because that's how you could end up dead....there could be earth leakage nothing more than a few volts...prove
the continuity of the earth cable ensuring it is connected to earth at the circuit end and start but I wouldn't rely on a neon screw driver deffinetly not

Another thing with out getting to technical it could be that your incoming system is a combined neutral earth system (TNC-S) or (PME) meaning the neutral and earth share a conductor back to the main transformer this could be causing the leakage down the earth it may be coming from outside your instalation like I said prove the continuity of your earth cable with in the lighting circuit ensuring that all earths are connected to earth

 

[Manchester_lalala]

This is called eddy currents mate, when the voltage passes through into another conductor (although minimal). When using a light pen, suspected dead cables are sometimes shown live as the cable is around live ones. If its saying 0v on your tester then it's dead, never trust a pen tester haha!

 

[Rascal]

A wise old spark once said to me. "i have papers to prove i can get electrocuted, you havent, so dont fuck with them"

 

[Swordfish7]

Thanks for the replies guys.

I connected a cable to the earth in the upstairs switch down to the consumer unit and did a continuity test between the earth and the main earth - Nothing (except a little spark). So looks like the the upstairs lights are not earthed.

 

[Feed-The-Goat]

stick your tongue on it, see if you get a shock maybe?

 

[ciderjohn1]

stick your tongue on it, see if you get a shock maybe?

bwahahaha

 

[blackley macca]

Never trust them light up screwdrivers, bad news.

 

[marco]

slightly of thread but how can 240 volts in a house can kill you yet a stun gun (tazer) can give 50,000 volts and just stun you allways wonderd about this

 

[Fitton]

slightly of thread but how can 240 volts in a house can kill you yet a stun gun (tazer) can give 50,000 volts and just stun you allways wonderd about this

It's not the voltage that kills you, it's the ampage.

High volts at a low amp will give you a nasty shock, low volts at a high amp can kill you.