Decorator getting Electric Shock from wall

[Newpark7]

Good evening all

Called out today to a rural bungalow where the decorator reported to the owner he had received an electric shock from the wall whilst sanding and refused to continue.

Installation consisted of TNC-S system, Wylex BS3036 rewire-able fuse box, no bonding to water or oil services, brass class1 socket outlets.

Carried out ZE 0.2 ohms
carried out Zs on socket outlet on suspect wall >2000
Isolated & removed cables at fuse box cpc proved open circuit.
Cable tracer transmitter connected at socket outlet and into the loft we go, traced fault to disconnected cpc in jb in loft.

Re-connected cpc & re-tested all ok

Customer has now given me the go ahead to replace fusebox & upgrade earth & bonding etc.

My question is as follows: -

If an electric shock was received surely that means that voltage/current was leaking to earth (if it had been in place)
Does this mean the new CU with RCD protection is likely to trip or is it normal for a small amount to leak to earth (obviously less than 30ma) and would this be enough to give an electrical shock?

All advice welcomed as always.

Thank you

 

[bugsy]

How was the decorator getting a shock?
Was his sander an old metal one?
Was his sander plugged into the socket with no cpc?

As far as changing CU - All the usual testS.

 

[SPARTYKUS]

Wet wall? N-E fault would do it.

 

[Newpark7]

Hi

Thanks for reply apparently just hand sanding.

 

[DurhamSparky]

possibly an accessory that has been "taped up" and shoved in wall..!!

 

[bugsy]

Must have been 5pm and he thought it was 3pm - that was the shock 2 hours drinking time gone!

 

[DurhamSparky]

hahahahahaha!!! you were not a bugsys rewire job were you by any chance!! another claim against the landlord!!

 

[Geordie Spark]

possibly an accessory that has been "taped up" and shoved in wall..!!

I'm busy just now rewiring my girlfriend's house & today discovered 2 core flex buried diagonally in 2 dining room walls to power 2 wall lights - which are both metal & un-earthed.

The ends of these wires are terminated by twisting the ends together, wrapping with tape & burying them in a 16mm deep backbox - with a piece of cardboard for a cover, then wallpapered over!!

Needless to say it's been disconnected now!!

 

[T&Earth]

hi Newpark

Thanks for the tips on sorting out this type of problem, could you please tell me what cable tracer you use.
Many Thanks
Steve