Kehui Power Cable Fault Locator - Advise On Similar Equipment

Not exactly my field, but TDR technology is supposed to use reflection delays of a ULTRA FAST rise time pulse and by using the known propagation speed, calculates the anomaly's distance. I really can't see how you can send a pulse like that to one of a parallel running bunch of conductors and expect it not to be coupled at least partly to the others. I stand to be corrected by others more experienced on this. S.M.

What happens when one digs a hole [carefully] at around 196 meters? This operation would prove the accuracy of the meter!

Correct,, ie. Lightening arrestors, PF inductors/caps..

...196m sounds like 200m to me with 2m chopped at each end for termination ie the length before the first drum splice perhaps....

Have you set the range, velocity and gain correctly?

Are you using it in auto mode? Try manual detection per page 10 of the manual...

2) Manual DetectionIf the automatic detection result is not ideal, please detect the fault manually.Press ADJ button to enter this menu, press GAIN+, GAIN,BAL+ or BAL,till getthe satisfactory waveform, and the distance to fault will be displayed.

Dear philpy,

May please note that before use of cable fault location by TDR set, please measure fault resistance i.e., resistance between conductor of faulty phase to earth(armour,if armour is earthed). As per engineering practice/ theory, TDR set can show earth fault(inverted loop) if the fault resistance is within five times of characteristic impedance(surge impedance) of the cable. You have not mentioned the above resistance in your post.Also the type of cable insulation is very improtant to fixup velocity propagation factor in the instrument before fault location.The above value is changed with the age of the cable. Therefore, before providing any comment/solution of the issue, the above informations are required.

Thanks,

Manindra.