How much distance does the power trough and the power trough intersect?
1 data line is broken 2 interface bad 3 bad contact
The cable armor will not have the other; if there is no need to wear pipe, but also need to consider the distance from the ground and the role of the ground above.
Wire leakage is the insulation resistance is reduced, you can use the multimeter's highest resistance file measurement of two non-connected wire resistance between the value should be infinite, otherwise the leakage. Statement: This method can only be rough measurement, not entirely accurate, after the measurement had to shake the table and other instruments to accurately measure
