Besantek BST-MGR01, Инструкция по эксплуатации

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BESANTEK
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9. 4 Terminals Measurement
C1 TP1
P2 C2
U s i n g the 4 T m et ho d , Re, ,. , R
e
,. does not affect
the r ead i n gs R " ' a n d R
m
are n eg l igea b l e as no
c u rre n t g o es i nt o P1 a n d P 2 .
For measuring low to very low resistance (contact resistance), this
is the preferred measuring method because the resistance of the
test leads does not have an effect (negligeable) on the measuring
results.
R
C1L
is the Resistance of the Current Lead going to C1
Rc
2
L is the Resistance of the Current Lead going to C2
R
P
1
L
is the Resistance of the Current Lead going to P1
R
P2L
is the Resistance of the Current Lead going to P2
The input impedance between P1 & P2 is 1 OM ohms, so because
the current being drawn by these pins is so small, the voltage loss
on R
P 1 L
+ R
P
2L is very small too.
So the loss in these potential wires is not even influencing the
voltage measured on P1 P2.
Due to the fact that the tester has a constant current source,
the current flowing between C1 to C2 is constant. Provided the
resistance of the current leads are reasonably low (low enough
for the current regulation to still be able to regulate properly), the
measurement using this method will give the bet results of all the
methods.
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