Appendix
EN
HBT3000 series user manual
Copyright © Qingdao Hantek Electronic Co., LTD
64
11.2
Appendix B: AC Four Terminal Test Method
This series of internal resistance testers adopts the AC four terminal testing
method, which deduces the wire resistance and contact electrons between the
wire and the test object during the measurement process, making the
measurement results more accurate.
Figure 11-1 Principle diagram of measurement method
Principle of AC four terminal measurement method: As shown in the figure, the
AC current IS is input to the measured object through the current output terminal,
and the voltage drop VIS caused by the impedance of the measured object is
measured on the voltage measurement terminal. At this point, the current
terminal is connected to the internal high impedance voltmeter, so there is almost
no current flowing through the resistance R2 and R3 of the wire resistance and
contact resistance, eliminating the voltage drop on R2 and R3, making the
measurement results more accurate.
