4. SPECIAL APPLICATIONS
4.12 Signal Clamp - Closed Loop Circuits
Closed loop, De-energized and low impedance circuits
The clamp accessory is used for applications where there is no access to a bare conductor
to connect the test leads. When the clamp is connected to the Transmitter, it enables the
Transmitter to induce a signal to the Energized or De-energized wire through the insulation.
Typical applications of the Signal Clamp include tracing conduits or shields grounded on
both ends. For signal cables and De-energized wires or loads, temporarily ground the circuit
on both ends to perform tracing.
Connecting the Signal Clamp
1. Connect the CT-400 test leads to the terminals of the Transmitter (polarity does not matter).
2. Clamp the CT-400 Signal Clamp around the conductor. To increase the signal strength,
wind a few turns of the conductor wire around the clamp if possible.
Set up the AT-8000-T Transmitter
1. Press the power button to turn on the
Transmitter. The red LED voltage status
indicator should be OFF when the clamp is
connected and when working with either
Energized or De-energized systems.
2. Press HIGH signal mode and hold button for
>2 seconds to select the Loop mode on the
Transmitter. This clamp mode (loop mode)
generates a boosted 6 kHz signal in order to
provide superior tracing results.
Figure 4.12a: Signal Clamp connection
28
AT-8000-T
TRANSMITTER
HI
LO
Figure 4.12b: Transmitter indicator
showing signal in Loop mode