Probing Principles
Probing Principles
The following information is provided to help you use the full potential of your current probe.
Degaussing a Probe with an Unpowered Conductor in the Jaws
You can degauss your current probe while a conductor of an unpowered circuit is clamped in the jaws. The advantage of
degaussing with an unpowered circuit is that any offset from stray DC magnetic
fi
elds is compensated. Degaussing with the
conductor in the probe jaws eliminates the need to manually remove the probe.
NOTE.
Be certain that the conductor in the probe jaws is completely unpowered. Any current
fl
owing through the conductor will
cause a residual offset in the current probe and may cause an inaccurate measurement or an error condition.
The impedance of your circuit should be higher than 10 m
Ω
for the degauss procedure to work. (The probe core might not saturate
with a circuit impedance of less than 10 m
Ω
). While degauss occurs, the probe will induce a signal of about 50 mV into 50
Ω
, at
about 170 Hz in the unpowered circuit. Your circuit must be able to absorb this induced voltage. With low impedance circuits,
several amperes may be induced in the circuit being measured. This may be of concern when you are using very small conductors.
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20 A Current Probes Instruction Manual
