B&K Precision 886 - Manual - Manual (Page 36)

33
(d) WRONG 4T CONNECTION
H
POT
DUT
(b) BLOCK DIAGRAM (a) CONNECTION
(c) TYPICAL IMPEDANCE MEASUREMENT RANGE (£[)
5T
1m 10m 100m 1 10 1K 10K 100K 1M 100 10M
H
CUR
DUT
V
A
DUT
V
A
L
POT
L CUR
Figure 3.4
 4-Terminal Path (4TP)
4-Terminal Path connection solves the problem that caused by
the test lead inductance. 4TP uses four coaxial cables to isolate
the current path and the voltage sense cable (Figure 3.5). The
return current will flow through the coaxial cable as well as the
shield. Therefore, the magnetic flux that generated by internal
conductor will cancel out the magnetic flux generated by
external conductor (shield). The 4TP connection increases the