underground swa faults

What methods have you found reliable
Anyone recomend any good methods /techniques/eguipment or know where to find some.

Looking to find advise on best way to find faults on under ground swa in various car parks, Up to 16mm usually.

usually no drawings and no visible cable ducts, pits,etc

Used sons , cat and the fluke 2042 £300 tester, just cannot seem to master it

I believe there may be courses on this.
Thanks

it depends on what faults you are looking for..

a short can be found by measiring the resistance of the short and dividing it by the combined resistance per meter of both conductors..
this gives you an approximate distance to search at.. ( no good if you don't know the rough direction.. )

a break you can get a meter that "pings" the cable. something like a sonar on a submarine.. it send a short pulse down the cable then looks for it to "bounce" back to the meter.. it then works out the distance for you.. ( again np good if you don't know the direction.. )

for tracing cables in general. you can get a cable finder system that comprises a signal generator and a hand held part for following the cable.. ( similar to a metal detector in operation.. .. also capable of finding a live wire without the generator.. )

That is the main problem we never really know the direction,

Imagine a tesco carpark , about 10 lights on the circuit , usually tripping mcb, we isolate each light , and if not clear break down the circuit all very time consuming.
Usually get down to a 10metre section

When the fault is between two posts in line not to bad .
But usually the route not obvious and we need to make a decision before getting it dug out

We clip on the transmitter ,but find it induces signal into the other cables in same duct, leading us the wrong way
I am sure there is an art to it somehow.