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2 vLoc3-9800 Receiver
2.14 Tracing a Buried Line
Where possible trace out from the transmitter connection point. Having
pinpointed the line, hold the locator vertically and in front of you with
the compass line indicator pointing forward/back. Start by moving the
locator left to right/right to left over the line. Keep the movement over
the center of the line, i.e., the largest meter response, adjusting the gain
when necessary. Whenever practical it should be traced to the point that
provides additional confirmation of what type of service is being located,
i.e., a telephone pedestal, a manhole cover, etc.
2.15
Pinpointing & Confirming the Buried Line
Marking the exact position of the buried line is generally called
pinpointing. Pinpoint the line before marking its position. Place the
receiver in “Manual Peak” or “Left/Right” mode, pass the blade of
the receiver across the path of the cable and identify the position as
indicated by the largest signal or as indicated by the Left/Right indicator.
Use the “Compass Line Direction” indicator to confirm the line is exactly
forward/back.
2.16 Depth & Current Measurement
• Pinpoint the cable as described in section 2.10.6, “Pinpointing & Confirming the Buried Line,” with the receiver in line with and
directly above the buried line – measure the depth (d) by pressing the “i” pushbutton briefly. Unless configured differently, the
current will be displayed at the same time as the depth.
• Be careful when locating in congested areas or close to bends or T’s. They may be inaccurate due to distorted fields.
(a)
(b)
(c)
d
d
d
d
d
d
d
65ft
(20m)
• An alternative method of verifying depth is triangulation which can be
done in the “Manual Peak” mode.
1. Pinpoint the line as previously described. Adjust the gain so that
full-scale deflection is just achieved.
2. Move to one side until the meter deflection (using the numeric
display may be easier) reads 70% (700).
3. Mark that position, then repeat on the other side.
The distance between the two 70% marks will be the same as the depth
of the line.
Distance A to B = Depth (D)
