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78-9000-5020-0 Rev C
Step 7.
Continue along the cable path, re-inserting the 3M™ Earth Contact Frame
probes every few steps while watching the receiver bar graph. The bar graph on
the receiver will fill toward the right side of the screen (green), indicating that
the fault is ahead of the operator (in the direction of the green-banded leg of the
Earth Contact Frame).
Transmitter Signal
Green Band
Red-and-White-Striped Band
Step 8.
When the bar graph fills toward the left (red-and-white-striped) side of the
screen, the fault has been passed and is now behind the operator. Move back,
inserting the Earth Contact Frame every few inches, until the arrows alternate
back to green. Mark the point beneath the center of the Earth Contact Frame.
Turn the Earth Contact Frame 90 degrees and insert into the ground over the
previously marked point. Move the Earth Contact Frame to the left and right
(following the directions of the green and red arrows). When the arrows reverse
a third time, turn the Earth Contact Frame 90 degrees again. Pinpoint the fault
by moving the Earth Contact Frame in the direction of the green and red arrows.
The fault is located beneath the center of the Earth Contact Frame when the
arrows change from one side to the other this time.
Step 9.
To verify the fault location, insert the Earth Contact Frame’s red-and-white-
striped probe directly on the spot identified above. Pivot the Earth Contact
Frame in a circle around the red-and-white-striped leg re-inserting the green-
banded leg in the ground every few degrees of the circle. The arrow should
always point toward the left (red) indicating that the fault is directly below the
red-and-white-striped leg.