|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
2. Dug up fault location, but found no fault.
A. If unjacketed concentric neutral, concentric
neutral must be used to pinpoint fault
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.