RD5100H
2
O+ Operation Manual
© 2018 Radiodetection Ltd
19
Section 5 Locating cables and pipes
This section introduces the principals and techniques of locating buried cable and pipe utilities with the RD5100H
2
O+
system. For more information on the theory of cable and pipe location, refer to
ABC & XYZ of locating buried pipes and
cables
, which is available to download from
5.1 Frequencies
The RD5100H
2
O+ locator supports a range of active and
passive frequencies.
For a complete list of supported frequencies, refer to
Passive frequencies
Passive frequency detection takes advantage of signals
that may be present on buried metallic conductors. The
RD5100H
2
O+ locator supports two types of passive
frequencies:
Power
and
Radio
signals.
You can detect these frequencies without the aid of a
transmitter if they are present on the utility you are
surveying.
Active frequencies
Active frequencies are applied to a buried conductor
using the transmitter. The transmitter can apply a signal
using three methods:
Direct Connection
In Direct Connection, you connect the transmitter output
directly to the utility. The transmitter will then apply a
discrete signal which you can locate using the locator.
This is the preferred method of applying a transmitter
signal to a utility and in the majority of applications will
apply a stronger signal to the utility, which may increase
the locate distance.
To directly connect to a non-energized conductive utility:
1 Switch the transmitter off.
2 Connect the Direct Connection lead into the
transmitter accessory socket.
3 Clip the red connection lead to the utility ensuring
that the area around the connection is clean and that
a positive connection is achieved.
4 Clip the black connection lead as far away as
possible and at 90° to the ground stake or suitable
ground point nearby ensuring that a positive
connection is achieved.
5 The display will show the Direct Connection lead
connected icon.
Figure 5.1 - Direct connection lead icon
For more information about other signal connection
accessories, refer to Section 8.
WARNING: Direct Connection to live conductors is
POTENTIALLY LETHAL. Direct connections to live
conductors should be attempted by fully qualified
personnel only using the relevant products that allow
connections to energized lines.
WARNING: The transmitter is capable of outputting
potentially lethal voltages. Take care when handling the
terminals, connection leads and ground stake, notify
other technicians working on the line of the hazard and
guard exposed conductors to prevent accidental contact.
Induction
In this mode of operation the transmitter is placed on the
ground over or near the survey area. If a Direct
Connection lead or signal clamp is not plugged into the
transmitter, it will automatically go into induction mode. In
this mode, only frequencies applicable for induction mode
will be made available as the
key is pressed.
Once activated the transmitter will induce the signal
indiscriminately to any nearby buried conductors.
Please note that these signals will also be airborne and it
is advisable to keep the distance between the transmitter
and locator at least 10m / 30ft
– this distance may need
to be increased, particularly if depth measurements are
taken.
Signal clamp
An optional signal clamp can be connected to the
transmitter and clamped around a cable or pipe to apply
the transmitter signal. This method of applying the
transmitter signal is particularly useful on insulated live
wires and removes the need to disconnect the supply to
the cable. Clamps are available up to 215mm /
8.5” in
diameter.
WARNING: Do not clamp around uninsulated live
conductors.