Hi

I have already mention about locating "Cable Fault " in the underground Cable.

I will once againg give details of the test result and cable details below.

Total Cable Length - 160m(GIS Basement - Transformer)

132Kv,cu,1c,800sqmm, Manufacture - ILJIN(Korea)

1) we want to locate the fault on this cable which runs from GIS basement to Transformer.

2) The first test that done was sheath test using shrila kit-, BY injecting 10kv dc, voltage break down at 5.5kv, current 4.3ma,resistance 2mohm.

3) we tried was PIN -POINT method, BY injecting 10kv dc to find the fault signal, But we do not get the fault signal at any point on the cable(GIS - Transformer).

4) But at some 40m from the GIs end, there was a small deflection on the receiver, but above that exactly 132kv OHL line passes, so we can't conclude that was a fault signal..

5) Then we tried with Murry Loop Method, At GIS end, the distance showed are 6.8m, 20.5m, 13.6m, 4.6m, 149.2m, 150.7m. etc on repeating the test(Interchanging k1g1 & k2g2).

6) On the Transformer End, the values are 7.8m, 11.3m, 5.9m, 31.2m, 20.6m,1m ((Interchanging k1g1 & k2g2).)etc…

7) We are unable to arrive to a final solution at this place will be the exactly fault will be on the cable.

8) Some time the cable withstand the 10kv dc if we are continues injecting the voltage by PGK 50 kit

Important Note :

After the first break down, the maximum current showed on all the test are 0.3A, some time 4.5A

4Mohm, The minimum there has to 1 Gohm

Say Suppose, If the problem is in Link Box or At the Cable Termination.

If so, how the problem has to be Indentified. "Link Contact Resistance Test" will help at the Link Box.

What are the testing methods and testing Equipments at the Termination Side.

will any one give clear solution for this.