IET Labs DE-5000, Руководство пользователя и обслуживания

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1.2.2. Measuring impedance
Impedance can be measured in series or in parallel. In parallel
mode, impedance can be represented as reciprocal of admittance
( Y ). The admittance can be defined as Y = G + j B , where:
G = Conductance
B = Susceptance
Series impedance Parallel admittance
To understand the ratio of resistance and reactance, it is
important to consider two factors: quality factor ( Q ) and
dissipation factor ( D ). Usually Q is used when measuring
inductance and D is used when measuring capacitance. D is
defined as the reciprocal of Q .
Q = 1/ D = tan
Θ
Q = Xs / Rs = 2
π
f Ls / Rs = ½
π
f CsRs
Q = B / G = Rp /| Xp | = Rp /2
π
f Lp = 2
π
f CpRp
Rs
= Series resistance
Xs
= Series reactance
Cs
= Series capacitance
Ls = Series Inductance
Rp
= Parallel resistance
Xp
= Parallel reactance
Cp
= Parallel capacitance
Lp = Parallel inductance
Y = 1/ Z = 1/ Rp + 1/j Xp = G +j B