Vivax Metrotech 4.04.000170, User Handbook Manual

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3 Using the vLoc3 RTK-Pro
• Measure the buried line's depth by pressing the “i” pushbutton briefly to measure depth and current. The depth should be
approximately in line with the “as-built” plans available. If no plans are available, logic would still help assess the situation (for
instance, if you are looking for a shallow CCTV distribution cable and the depth indicated is 5-feet
(1.5m)
, it should raise a
concern).
• Take a depth reading on the ground and then raise the locator approximately 1-foot or 0.25m and repeat the depth
measurement. The depth should increase by this amount. If not, treat the information with caution.
• A depth reading on congested areas or close to bends or tees may be inaccurate due to distorted fields.
d
d
d
d
d
3.9 Sonde Location Mode
A Sonde is typically used for locating non-metallic pipes or ducts or the camera end of a sewer inspection camera. Low-
frequency versions (512Hz/640Hz) can transmit through some metallic pipes such as cast iron pipes which is why they are
frequently used with sewer inspection cameras.
The Sonde Location mode is a Peak mode which means that the bar graph and audio will grow when approaching the sonde
and at their maximum when over the sonde.
Sonde screen:
67.2
25dB 8kHz
4G
2 2
3 4 5
6
8 7
1
1 Peak signal detector
2 Signal strength bar graph
3 Sonde icon
4 Null point
5 Direction to sonde
6 Frequency selection
7 Numeric signal level (mirrors the bar graph)
8 Gain setting
The Sonde transmitting coil radiates differently than that of a line.
Due to this construction, the sonde gives a different “Peak” pattern note
that there are three distinct peaks – a small peak – a large peak – a
small peak with two “Nulls” between the peaks. The sonde is located
under the center of the “large peak.”
The vLoc3 receivers detect the two “Null” signals and the position of
the main “Large Peak.” It uses this information to provide a reliable and
efficient method of sonde location.
NULL NULL
MAIN PEAK