Radiodetection RD4000T10, Руководство пользователя

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RD4000 Locating System User Manual
Page 56
Preparation
Insert a new battery into the sonde. A new battery or a freshly recharged battery should be used at the
beginning of each day and preferably at the start of each new job.
Before inserting the sonde, check that the sonde and receiver are at the same frequency and working correctly.
To do this, place the sonde on the ground at a distance from the receiver that equal to the rated depth of the
sonde. Point the receiver at the sonde with the antenna in line with the sonde (the opposite of using the receiver
to locate a line) and check that the bargraph reading exceeds 50% at maximum sensitivity.
Propelling a sonde
Sondes have a male thread at one end for connecting to drain rods, or to other devices for inserting and
propelling the sonde along a drain or duct. Sondes may be floated along drains at the end of a tether and floats
are available for fitting to the sewer sonde and super sonde. Sondes can be strapped to high-pressure water
jets or similar devices used for cleaning, maintaining and inspecting drains. Sondes used in underground drilling
and boring operations are normally housed in the boring or drill head behind the boring or drill bit.
Locating and tracing a sonde
Insert the sonde in the drain or duct access and locate it while it is still
just in view at the drain or duct entrance. Hold the receiver vertical
directly over the sonde with the antenna in line with the sonde. Adjust
the receiver sensitivity so the bargraph reads between 60% and 80%.
The sonde radiates a peak field from the centre of its axis with a ghost
signal at each end of the peak. Move the receiver a little way behind
and then in front of the axis of the sonde to detect the ghost signals.
Finding the two ghost signals positively confirms the locate. Reduce
the receiver sensitivity to lose the ghost signals but still indicate a clear
peak response directly over the sonde. Receiver sensitivity is now set
for tracing the duct or drain unless the distance between sonde and
receiver changes.
Propel the sonde three paces along the drain or duct and stop. Place
the receiver over the supposed position of the sonde. Do not adjust the
sensitivity level.
1. Move the receiver backwards and forwards with the blade in line with
the sonde and stop when the bargraph indicates a peak.
2. Rotate the receiver as if the blade is a pivot. Stop when the bargraph
indicates a peak.
3. Move the receiver from side to side until the bargraph indicates a
peak.
4. Repeat 1, 2, and 3 with the antenna vertical and resting on or just
above the ground. The receiver should then be directly above the
sonde with the antenna in-line with it. Mark the position of the sonde
and its direction.
5. Propel the sonde a further three or four paces, pinpoint, and mark the
position. Repeat this pinpoint procedure at similar intervals along the
line of the drain or duct until the survey is completed.