English
3.1.3
THE NEXT STEP : THE 2 TRANSMITTER CONNECTION MODES
Only these transmitter connection modes can be used to locate conductors with
the LOCAT_NG
Single-pole application:
Connect the transmitter to a single conductor. If the signal transmitted by the
transmitter is a high-frequency signal, only one conductor can be detected and
traced.
The second conductor is then earthed.
This arrangement causes the flow of a high-frequency current in the conductor
and its transmission through the air to earth; this is the same principle used
between the transmitter and the receiver for radio broadcasting.
Two-pole application:
This connection can be made to a live or dead mains line. The transmitter is
connected to both conductors using the two test leads.
A Connection to a live line:
Connect the "+" terminal of the transmitter to the conductor connected to the
•
phase
Connect the other terminal of the transmitter to the neutral line of the mains.
•
In this case, if there is no load on the mains, the modulated current from the
transmitter will flow to the neutral line by coupling via the distributed capacitance
of the wires of the line and then return to the transmitter.
Remark:
When the transmitter is connected to a live line, if one of its terminals is connected
to a protection earth wire rather than the neutral, the current through the
transmitter is added to the leakage current already present in the installation. The
resulting total leakage current may then activate the RCD, in other words trip the
RCD.
B Connection to a dead line:
Connect the "+" terminal of the transmitter to one wire of the line,
•
Connect the other terminal of the transmitter to the other wire of the line, and
•
then
At the other end of the line, connect the two wires together.
•
In this case, the modulated current returns directly to the transmitter through the line.
In another method, the two test leads of the transmitter can be connected to the
two ends of a single wire. In addition, since the installation is dead, the protection
earth conductor of the line can also be used without risk.
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C.A 6681 Cable Locater