Radiodetection RD4000T10, Руководство пользователя

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RD4000 Locating System User Manual
Page 27
To select a peak mode:
•
Press and release the on/off key to switch the receiver on
•
Press the antenna select key until the required peak mode is displayed.
Use wide band if the pipe or cable is too deep to be located using the narrow band antenna. Wide band will
locate the pipe or cable but will not pinpoint it. In wide band, it is not possible to take a depth reading.
Selecting null mode
To select null mode:
•
Press and release the on/off key to switch the receiver on
•
Press the antenna select key until null mode is displayed.
Null mode gives a null response when it is directly over the line. The sharp, null response is easier to use than
the peak response but is vulnerable to interference and should not be used for locating, except in areas where
there is no interference present. In null mode, the receiver will indicate line position but not its orientation.
Locating the cable/pipe
There are three techniques for locating pipes and cables. They are:
•
Trace
•
Pinpoint
•
Sweep and search.
Trace
Line tracing can be speeded up by switching the receiver to
null response.
Move the receiver left and right while walking along the path of
the line to observe the null directly over the line and a peak
response to each side of the line. As you move the receiver
over the line the left and right arrows indicate if the target line
is to the left or right of the receiver.
Periodically switch to peak mode, locate the target line, and
verify its exact position.
Pinpoint
Pinpointing a target line in peak, narrow mode, defines the exact position of a target line after it has been traced
and its position is approximately known. Start with medium output power from the transmitter, medium
frequency on the transmitter and receiver, and peak mode on the receiver.
Set the receiver sensitivity to half scale.
Note: it may be necessary to adjust the sensitivity level throughout the pinpointing to keep the bargraph on scale.