TIMCO INSTRUMENTS,LLC

Typical Field Fault Locating Problems
The success in using the SPITFIRE is in the understanding of a voltage gradient system and the fact that the instrument cannot deliver false information. If the instrument is connected correctly, just move in the direction indicated by the Detector and you will put an "X" on the ground over the fault. Listed below are several problems and possible solutions encountered in the process of fault locating.

1. Detector needle fails to deflect when impulsed.

A. Check SPITFIRE Transmitter output into cable
B. Check cable connections
C. Is the cable a faulted cable?
D. Check Ground Probe leads
E. Replace 9 volt Detector battery
F. Cable is in dry conduit (i.e., under a driveway, etc.)
G. Fault is not making contact with earth

2. Dug up fault location, but found no fault.

A. If unjacketed concentric neutral, concentric neutral must be used to pinpoint fault
B. Porous insulation.

With the cables exposed, reduce the Detector sensitivity to a very low level, lay the probes directly on the damp cable surface. Move the probes around until a "null" occurs. This type of condition generally happens with copper conductor street light cable. Wipe the cable surface clean with solvent, and wipe dry. Cover the leakage area with several layers of a high grade plastic electrical tape. Cover with damp soil and use the SPITFIRE to determine if the cable fault still exists.

This type of fault can also occur with aluminum conductor cable, but it is quite rare. This type of fault may be identified while looking for a major failure. All failure locations must be repaired.

C. At the fault location, only a copper water pipe was found. The cable is faulted to the water pipe providing additional false fault locations. Be sure you are digging on the cable route.



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