Hello all, hoping to get some input on a cable problem. Have a 2C SPC8 cable running u/g for ~6750 ft. It has recently shorted to itself, not to ground. (Meggared) Resistance readings of the cable open on both ends are 4.4 Ω from the east end and 4.64 Ω from the west. Doing the math and assuming a dead short, the short should be 48.7 % the length of the cable from the east end. Took a TDR and shot the cable from each end, using a VOP of .71 (just guessing), got readings of 4468' from the east end and 4681 from the west, (means the VOP was wrong), but makes the math jive with the resistance tests. Digging up at the surmised spot(4' down), the resistance was ∞ to the west and 0.8Ω to the east. Another TDR shot shows the fault ~600 ' to the east.
I tried using a cable locator/faultfinder to try to locate the short, but since it is not to ground, the faultfinder doesn't see any problem. I have loacted it np, it runs right along the railway, so I know exactly where it runs. I tried hooking the + of the transmitter to one wire, and grounding the other, and grounding both the wires at the far end and hooking the locator up in the CD mode, hoping to see the current direction change, but to no avail. Running out of ideas... Anyone????
I tried using a cable locator/faultfinder to try to locate the short, but since it is not to ground, the faultfinder doesn't see any problem. I have loacted it np, it runs right along the railway, so I know exactly where it runs. I tried hooking the + of the transmitter to one wire, and grounding the other, and grounding both the wires at the far end and hooking the locator up in the CD mode, hoping to see the current direction change, but to no avail. Running out of ideas... Anyone????