Aqua-Tronics S.D.A.D.II, Operator'S Manual

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ground rod. A small magnetic wave will be between the cable fault and the ground
rod at the far end of the cable. AS A RESULT, THE OPERATOR SHOULD SEE A
REDUCTION OR COMPLETE LOSS IN BALLISTIC IMPULSE LEVEL WHEN THE
FAULT HAS BEEN PASSED.
NOTE:
Isolating the neutral at the far end of the cable on a jacketed primary will
remove that current path and the magnetic fall off will be much more abrupt at
the fault. Isolating the far end ground rod on a direct buried (NON-JACKETED)
primary may help, but because the neutral is still in contact with the soil the fall
off may not be as abrupt.
QUICK SEARCH WITH BALLISTIC IMPULSE ONLY
AUTOMATIC BALLISTIC CALIBRATION
1. Move 20 feet away from the thumper and 5 to 10 feet off to one side of the
marked cable path. Turn on the SDAD
II
electronics.
See Figure 5
2. Start thumping the cable.
3. After about 3 or 4 thumps, the ballistic impulse level will automatically set.
4. Walk the cable path maintaining the same approximate 5 to 10 feet distance
from the cable path. The ballistic impulse reading will be lost after passing the
cable fault. Mark this location.
5. Continue down the cable path 30 to 40 feet. If the ballistic impulse level does not
return, a microphone placed at the pre-located spot and is usually close enough
to hear the thump.
Figure 5