80 volts ac on earth cable

[onesongrg]

? not seen the job as yet, friend tells me he swoped over a security light, it did't work so he checked for voltges on the cable. There is 80 volts ac between live and earth and 80 volts between neutral and earth i told him to do a continuity test from the earth to an earth on a socket were he says it is open circuit, all the lights are working else were.
Will be looking at it on monday.
Any ideas were 80 volts ac is coming from ?

 

[plugwash]

seems like there are some breaks in the wiring somewhere

could be a nightmare to trace though

 

[ban-all-sheds]

1) Is he measuring with a DVM, or an analogue meter?

2) Is the light switched by a PIR?

 

[onesongrg]

A pir sec/light, i would say since he is a bt engineer i would say bt analogue tester.

 

[supersparks]

ive found timer fans to give about that
although, across earth is worrying.
but, alot of people, unfortunatly dont connect earths on lighting circuits.
you will have fun there