SPX CUES ACCUPOINT MS611, Руководство пользователя

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19
Locating pipes with a sonde
NOTE: The 'blade' of the locator must be in-line with the central axis of 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 a job. Check that the locator and sonde are working
correctly.
A quick test for both sonde and locator
is to position the sonde at ground level
at a distance equal to its rated depth
range from the locator. Point the locator
at the sonde with its blade in-line with
the sonde, and check that the bar graph
on the locator displays more than 50%
with the sensitivity of the locator set to
maximum.
With the sonde in place at the survey
location, hold the locator vertically and
directly over the sonde's estimated position. Make sure the blade is in-line with the
sonde. Adjust the sensitivity (gain) of the locator to give a bar graph display reading
between 60% and 80%.
A sonde radiates a peak radio frequency
field from the center of its axis with
weaker signal (ghost) lobes at each
side. Ghost lobe identification helps to
confirm the accuracy of the peak (center)
position. Move the locator a little way to
one side and then along the axis of the
sonde iteratively forwards and backwards
to detect the ghost lobes. Reduce the
sensitivity of the locator until the ghost
lobes are no longer detected.
With the locator sensitivity set as desired,
propel the sonde along three to four
paces and stop.