It works for locating cables as well but not for finding faults. The DNO I used to work for had a divining set made by an instrument maker and we go good results with it. The water board used divining rods a couple of years ago to find the service pipe to my house. I have also used the bent wires to find field drains and services etc. My wife is much better at it than me, but she is a witch.
If its a good low impedance fault on the cable you can rig up a Wheatstone bridge to get an approximate length. aka Murray loop test
