Tektronix TCP0030, Instruction Manual

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Probing Principles
Extending DC Range
If you want to measure a low-amplitude AC component that is superimposed on an extremely large steady-state DC component
(such as in a power supply), or if you want to extend the DC current range of your probe, you can add offset (bucking) current with
a second conductor.
WARNING. Do not put more than one uninsulated conductor at a time in the probe jaws. An uninsulated conductor is any
conductor without insulation or without insulation rated for the voltage present on the conductor under test.
To supply additional bucking current:
1. Place a second conductor that has a pure
DC component of known value in the probe
jaw with the conductor under test.
2. Orient the second conductor so that the
bucking current
fl ows in the opposite
direction of the DC fl ow in the conductor
under test.
3. To determine measurement values, add
the value of the bucking current to the
displayed measurement.
30 TCP0030 Current Probe Instruction Manual