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N2780/1/2/3B User’s Guide
N2780/1B Current Probes
Current Direction Indication
Align the sensor so that the current direction indication corresponds to the
direction of current flow through the conductor to be measured.
Opening Lever
Opens the clamp. Always use it to open and close the clamp.
LOCK/UNLOCK Indication
Indicates if the sensor head is closed or open.
Demagnetizing Switch (DEMAG)
This switch demagnetizes the core if it has been magnetized by switching the
power on and off, or by an excessive input. Always carry out demagnetizing before
a measurement. The demagnetizing process takes about 3 seconds. During
demagnetizing, a demagnetizing waveform is output.
BNC Output Connector
Connect to the oscilloscope’s BNC input connector. Turn the collar until it clicks,
and check that it is locked securely.
NOTE
The output of the current probe is terminated internally. You must select
the input impedance of the oscilloscope to be 1 M
Ω
in order to make
accurate measurements. If the oscilloscope you are using does not have
a 1 M
Ω
input impedance setting you can purchase the E2697A 50
Ω
to
1 M
Ω
adapter.
Power Supply Cable
Connect the power supply cable to the N2779A Power Supply receptacle to
supply power to the sensor terminator.
