15 Volts Cause?

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sirsparkabit

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Got to quote for a couple of new lighting circuits.

Old ones have no earths and have been in since the fiftys, on checking a bit of the old circuit i find 15 volts at one of the lampholders.

Bulb had been changed to a low energy so when turned off the 15 volts made it flicker.

Four way wylex board

1 lighting circuit

1 immersion

1 ring

1 cooker

What is the most probable cause of this leak of current lads please. :)

 

sirsparkabit

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Thanks patch , you really are the No1 url finder.

That makes sense nowApplaud SmileyApplaud SmileyApplaud Smiley

 

Mr Sworld

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We get up to 24V on the neutrals at work. Lots of flourescents on the system mind you!

 
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Interesting problem, could be insulation breakdown, have you meggered it, is it rubber ?

Would a borrowed neutral cause that ? Is the polarity correct ? Is the switch damp or full of carbon residue due to age, hence passing a voltage ?

Would like to hear the outcome.

 
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Interesting problem, could be insulation breakdown, have you meggered it, is it rubber ?Would a borrowed neutral cause that ? Is the polarity correct ? Is the switch damp or full of carbon residue due to age, hence passing a voltage ?

Would like to hear the outcome.
if you had a borrowed neutral Deke, wouldn't you have nothing or a full 230V?

 
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Not necessarily a borrowed neutral can be taken of a power circuit.Batty
(bear with me here batty) I thought the 'borrowed' neutral was often from an upstairs lighting circuit on stairs lights? If you have 1 lighting circuit for 2 floors surley you'd borrow the neutral of that?

Are you saying what could possibly happen? Have you seen it?

 
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Borrowed neutrals are neutrals taken from other circuits. Could be a neutral taken from a power circuit. Probably unusual but we see all sorts. Nothing ever suprises me when diyers get involved and poor electricians. Lighting taken direct from power circuits with no spur not uncommen.

Batty

 

steptoe

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yep, I have seen once a heating system pump with the live taken from the ring and the N from the Imm heater,,,!!!! WTF,!!!

no idea why they didnt just take them both from the same circuit,

am guessing they originally took them both from Imm htr but then realised that sometimes the live wasnt, so simply stole one from a socket and simply left the N as was!!

 
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Got to quote for a couple of new lighting circuits.Old ones have no earths and have been in since the fiftys, on checking a bit of the old circuit i find 15 volts at one of the lampholders.

Bulb had been changed to a low energy so when turned off the 15 volts made it flicker.

Four way wylex board

1 lighting circuit

1 immersion

1 ring

1 cooker

What is the most probable cause of this leak of current lads please. :)
Some cheepo low energy bulbs can flicker on a bit after the power is switched off! :|

If your meter was not making a good neutral connection.. just a good contact with an energised live.. you can get anything upto "an apparent" 50v reading? ?:| :|

 
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