GW Instek LCR-800 Series - Manual (Page 65)

APPENDIX
129
Impedance (Z) and Admittance (Y = 1/Z) Formula
Background Impedance measures the total amount of
opposition between two terminals in an AC circuit.
Admittance is the reciprocal of Impedance and
measures how easily the electricity flows in an AC
circuit.
Note
Admittance is only shown for its relation to
impedance. Admittance is not measurable with the
LCR-800 series.
Type Impedance (Z) Admittance (Y)
Formula
Y I
E
Z
1
 
jX R Z
S
 
C
j
R L j R

    
 
2 2 X R Z
S
 
 
2 2 X R
RX
Z
P 

 cos Z R
S

 sin Z X
S

Z E
I
Y
1
 
jB G Y
P
 
L
j
G C j G

    
 
2 2 B G
GB
Y
S 

 
2 2 B G Y
P
 
 cos Y G
P

 sin Y B
P

LCR-800 User Manual
130
Quality factor (Q) and Dissipation factor (D) Formula
Background Both Quality factor and its reciprocal, Dissipation
factor, are used for measuring the rate of energy
dissipation relative to the measurement frequency.
 Low energy dissipation: high Q, low D
 High energy dissipation: low Q, high D
Type Quality factor (Q) Dissipation factor (D)
Formula
S S S
S
R C R
L
Q

 1
 
P P
P
P R C
L
R


 
 
D
1
90 tan
1



 
S S
S
S R C
L
R
D 

 
P P
P
P G L
C
G


 
 
Q
1
90 tan     