May I comment on the document provided by SouthwireSam and some of the reactions: The pages posted by SouthwireSam are from Southwire's Power Cable Manual 2005 (3rd edition)chapter 9 "Field Testing". Unfortunately, the pages do not reflect state of the art practice and are rather generic.
There...
If you are doing line design frequently, and prior to using a full-blown design package such as PLS CAD, also consider
http://www.sag10.com/
and, of course, as recommended before, the must have Southwire Overhead Conductor Manual
http://www.southwire.com/ordering/OCM.htm
Dear Submonkey,
You went through a lot of work to show that the sum of all induced currents in a fictitious conductor in position x is zero, under the condition that phases a,b and c are balanced and the sections of the system are of equal length. So far so good. The sheath or screen of any...
Not so fast. If the HV cables are single core and are installed with some spacing between them and may in addition the screens are single point or cross-bonded, there is a significant residual magnetic field as a result of the superposition of the magnetic fields of the individual cables.
If, on...
Answer is totally correct. Transposition of phases has nothing to do with elimination of circulating sheath currents that would derate the cable but is sometimes used to balance the phase characteristic impedances for long cable circuits.
Provided that the PD measurement did pick up PD from the termination and not from other sources (bus, transformer, bushings, etc), high level PD activity inside the termination would leave traces of PD, i.e. discharge marks on cable insulation or insulator surfaces or at interfaces such as...