RD4000 Locating System User Manual
Page 37
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If CD reset is successful, the screen returns to the normal locate screen.
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If CD reset not successful, ‘INFO 13’ is displayed, indicating that the receiver and transmitter
frequencies are not matched or the transmitter connection leads are wrongly connected.
Check that the receiver display indicates a forward pointing arrow after the reset and phase angle is 0
0.
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Reset the receiver CD reference each time the transmitter is turned off and on or the signal is disconnected
and reconnected or when changing from direct connection to a CD clamp.
•
Reset the CD reference at intervals of several kilometres/miles tracing distance or when a direction arrow
flashes off and on. This reset procedure can be carried out near a joint or splice box where the identity of the
target line is certain. Do not perform a CD reset over a splice box where cables may be looped.
When locating midway along a long line it may be difficult to define if the transmitter is ahead of or behind the
line when resetting the receiver. Find a nearby conductor with a visible identity to which the signal has coupled.
A railway line, a continuous metal fence, or highway crash barrier are suitable conductors. Make a CD locate on
the visible line. The arrow should point back toward the transmitter. Then pinpoint the target line to check that
there is a forward pointing arrow on the display.
•
Reset the CD reference after pinpointing the target line
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If a nearby line also radiates a transmitter signal, pinpoint it and activate the CD feature to establish the
current direction. The arrow will point back toward the transmitter if the signal has coupled to it from the
target line.
Because the cable shields are bonded and the outward CD signal travels over the bond, CD is only effective on
multiple cable installations as far as the following splice box.
Using a CD clamp or stethoscope
When using either of these accessories it is important to RESET the CD at a known point, near the transmitter,
before making any identification measurements. On both the CD/CM clamp and the CD stethoscope there is an
arrow that indicates which way the clamp or stethoscope is facing in relation to the transmitter. If the arrow is
pointing away from the transmitter when the CD reset is performed the receiver display shows 000 and the
bargraph reads 100%. If the arrow is pointing towards the transmitter, the receiver display shows 111 and there
is no bargraph reading.
Data logging
Using the data logging facility depth and current can be logged and transmitted to an external data logger or
Global Positioning System (GPS) device for later analysis. When logging data the external data logger must be
connected to the RD4000 receiver, as the receiver does not have an internal data log store. Connect the data
logger to the RD4000 receiver accessory socket by means of an RS232 lead.
Data is logged by means of the depth button as follows:
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Press and release the depth button to display the depth
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Do not touch any other button for five seconds and the depth and current will be automatically logged. After
this time the receiver will switch back to locate mode.
If you do not wish to log the data, press the depth button within five seconds to cancel logging. The receiver will
switch back to locate mode without logging.
