High earth loop readings

[duxter121]

Hope someone can help, I am an industrial biased electrician & a friend has asked me to check an outside tap on one of his houses where the tennant keeps getting a belt off the tap, the loop test at the board shown up 17.8ohms & was registered as dangerous on the tester (A Metrel tester)...
The supply I think...is a TT system or a TN-S, not got a regs book with me & not 100% on supply systems (which i'm reading up on now)..bad I know
Anyway, there is 2 cables run down the outside of the house & what looks like the earth is tapped off the neutral about 1 METER before the cut-out & disappears down the wall & under the decking....I do know that he had a dodgy spark do some work on it for him years ago & I have done some reading up on possibilities of what it could be & the only one I can think is that they may have used the other services, gas & water to bond the house
There is no earth at the cut-out or electric meter....

 

[TaffyDuck]

Dont forget static! If the outside tap appears to be only live sometimes this could also be a charged person. nylon carpets and socks inside straight into nice rubber wellies then outside into the garden and its not unusual that you are carrying a static charge yourself. Touching a well earthed outside tap will discharge the static you are carrying down the pipe or through the bond to earth and give the same sensation as a shock even though its the electricity is travelling in the opposite direction.

Not saying that it shouldn`t be checked, far from it, and an RCD install is very sensible advice, just saying that occasionally there can be no fault present.

 

[GLENNSPARK]

isolate the supply and remove bonding clamp (if any) from the pipework in question......then IR test at 500V DC between each final circuit in turn and the affected pipework.....if theres a breakdown in insulation..should find it......

 

[GLENNSPARK]

as the others have already said here.....theres a potentially dangerous situation here where if on a TT theres no RCD..often the only means of fault protection you have for rods......and you cant leave voltages sitting on pipework....even if only intermittent.......

 

[GT1]

As others have saidit needs a thorough investigation.. Good chance its an appliance somewhere gone to fault.
Last time I had a live water system on a house it was the garden pond UV light..!!