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To avoid the canceling effect of the opposing magnetic fields and optimize the
transmitted signal, the conductor to be traced should be separated from the return
conductor by utilizing a remote return path.
The simplest method is to use the 25’ test lead to connect to a remote return path, such
as a neutral or ground from another circuit or a water pipe. When identifying breakers,
the hot and neutral are already separated at the electrical panel so the use of the AC
outlet adapter is sufficient.
If unsure that the remote return path chosen is a good one, use a multimeter to measure
the resistance between the circuit neutral and the remote return path. If >100
Ω
, a
different return path should be selected.
Applications
Pre-test Operation
Prior to finding a breaker or tracing a circuit, it is good practice to test the receiver by
holding it near the powered transmitter or inductive clamp. A numeric indication of "99"
and strong audible sound ensures that it is working properly.
WEAK SIGNAL SETUP
SIGNALS CANCEL
Water Pipe
STRONG SIGNAL SETUP
NO SIGNAL CANCELING
Separate Circuit
Circuit
under
test
STRONG SIGNAL SETUP
NO SIGNAL CANCELING
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Locating Circuit Breakers and Fuses
Applications include identifying the breaker that protects the circuit under test, finding the
correct breaker to de-energize the circuit, and labeling a breaker panel.
1) Connect the transmitter to the circuit that needs to be identified and power it on.
The procedure is the same whether the circuit is energized or de-energized. But, a
much stronger signal is produced using an energized (closed) circuit.
2) Turn on the receiver and go to the panel.
a) If more than one panel exists, set the receiver to Search Low (SL/2) mode and
touch the nose to each panel cover until the panel with the strongest signal is
identified.
b)
If the receiver is detecting more than one panel with a strong signal, reduce the
sensitivity range to Trace mode (TR/3), and repeat the step above.
3) Open the panel cover, set the receiver to Breaker (BR/4) mode. The receiver should be
positioned on its side to orientate the antenna properly.
4) Slide the nose of the receiver down each breaker in the panel. The breaker with the
highest numeric reading is the correct breaker.
If two or more breakers have the same numeric values, tip the nose of the
receiver up and then down at 45º angles and note the numeric values on each of
the questionable breakers. Only the correct breaker will show a strong signal in
all positions. Or, pull the panel cover, and place the nose on each of the
individual hot wires for a more certain determination.
5) When the correct breaker is tripped (opened), the signal will drop significantly. And,
the will disappear from the receiver’s display (RC-958 feature only). The LED
on the transmitter will also turn off.
ND 6364-2 Circuit Tracer Instru 3/5/07 1:39 PM Page 11