Hioki BT4560 - Page 133

A3
Four-terminal Pair Method
In the four-terminal pair method, the current ows backward (current returns) with the same magnitude as the
measuring current in the shields of the SOURCE cables, and then cancels the magnetic eld of the measuring
current. This method suppresses the induced electromotive force induced at the SENSE terminals, and
detects the voltage actually generated in the object being measured.
Four-terminal pair method when using the optional probe
When the optional probe L2002 or L2003 of the instrument is used, the four-terminal pair method is structured
as described below.
It is necessary that the measuring current and the return current ow in close proximity to each other. This
structure enables the return cables to be easily brought close to the object being measured. It is important that
the shape of the return cable, which affects the magnetic eld, is not changed.
Measuring
object
SOURCE-H
SOURCE-L
SENSE-L
SENSE-H
V
A
Shield
Tip end: SOURCE-H
Tip end: SENSE-H
Return cable
Tip end: SENSE-L
Tip end: SOURCE-L
10
9
8
7
6
5
4
3
2
1
Appx. Ind.