Unknown damaged underground wire

[jasonpeace]

So where I've got my boat, the supply box to my boat has lost power, when the consumer unit was tested (each supply box has it's own consumer unit) if read approximately 2v ac on the input when this wire was removed its reads approximately 130v ac (not a stable reading) I assume its damaged underground in the recent cold (died when in minus temperatures)

the supply cable runs underground both through soft soil and concrete and tarmac the run most be between 300ft, is there a way to detect where its broken using a multimeter?

If so I'd like to be able to find the break location and fix it rather than wait 6-12 months for the land owner to actually look at it

 

[JohnD]

I'd start by examining the joints at each end, which are more likely to fail than the cable itself.

Once the supply is isolated, test between the cores to see if any of them are shorting.

If so, by testing the resistance between them at each end, it is possible to calculate the position of the fault.

This is harder with a buried cable than in a house, where you have multiple access points to test at every socket or switch.

Also look for signs of digging, new fence posts or other potential causes of damage.

 

[Rodders53]

More likely the RCD-MCB/fuse/switch at the site main or sub- distribution board has been tripped or isolated. Either deliberately or accidentally (possibly as a fault).

I'd use the term 'bollard' for the Boat's Plug/socket RCD/MCB setup (as per Touring Caravan sites) each bollard may be radial fed to a 'distribution box' on site or sometimes they are looped one to the next and back to a similar box. Marinas are not that dissimilar I believe.
Some caravan bollards include consumption meters nowadays, too.

You need to get the site operator staff / electricians to investigate the simple stuff before looking at faults on buried armoured cables I'd have thought

 

[ericmark]

These often come in two parts, and they can detect where the break is, they are rather expensive, so normally hired, there are cheaper versions, even my multi-meter can detect voltage with no contact at 4 levels, but this is unlikely to find the break in an SWA cable, the SWA its self shields the live wires, it is not unknown for a break mid-way along its length, but normally we find the break at the ends, I know I have a three core and earth cable with a faulty, so I just use 2 instead of 3 cores.

 

[jasonpeace]

Thank you for your replies, there is an "electrical shed" (shed describes the condition aswell) which none of the breakers tripped and the cables go directly through the shed "floor" to the "bollards" I'll speak to one guy who may know a little more about the system.

Unfortunately the owners changed hands a few years ago and the current owners dont really know anything about the layout and we already have a few posts which have died and been left for dead.

Theres been no digging on site we dont see humans or activity until at least May
I think it might have been temperature related as it died in the night when the temperature was in the minuses

I'll give testing the resistance at the ends a go
Baring that I think I might be looking for a 50ft extension to a working bollard