Vivax Metrotech vLocDM, Руководство пользователя

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Connect the transmitter to the pipeline to be surveyed as instructed in section “Connecting the Transmitter”.
Switch on the receiver and select the frequency to match the frequency selection on the transmitter. Stand
approximately 10 – 20 meters/yards from the transmitter and over the suspected position of the pipe. Stand
facing the transmitter and with the handle and display pointing at the connection point. See diagram below.
Keeping the receiver pointing at the connection point, walk around the connection point for a full 360
degrees. The reading on the receiver signal strength meter will rise and fall as it passes over:
• the two pipe locations (Forward and Aft)
• the cable running to the anode bed
It will be necessary to adjust the sensitivity of the receiver to keep the signal strength within the signal
strength scale. If the signal is very low on the scale, pressing the “+” pushbutton will adjust the gain so
that the signal strength is approximately 50% of scale. If the signal goes over the top of the scale press
the “-” pushbutton to return it to approximately 50%. Subsequent pressing of the “+” or “-” pushbuttons
will increment the gain.
Notice that as the pipe is neared the left/right arrow will point to the position of the pipe and the pipe
directions indicator will align itself with the direction of the pipe.
6.1 Locating a Pipeline
Using the vLocDM Receiver
6 Using the vLocDM Receiver
NOTE
There are a number of antenna configurations available. Each has a particular response.
However, for the purposes of simplicity the method below uses the generic “peak with left
right arrows”.