Sanwa LCR700, Instruction Manual, Page: 23 / 24

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The product specifications and its appearance described in
this manual are subject to change without prior notice for
improvements or other reasons.
Accuracy of D value De: De = ±Ae
Ae means an accuracy of rdg in the main display.
Ex. Capacitor to be measured: 180 nF
Test frequency: 1 kHz
Measuring accuracy: ±(0.3 %rdg + 3 dgt)
Ae = 0.3 %rdg
Calculation for De (Accuracy of D value):
De= ±0.003
Accuracy of ESR: Re = ±Z
M
×Ae(Ω)
Calculation for Z
M
: 1/(2πfC) or 2πfL
Ex. Capacitor to be measured: 180 nF
Test frequency: 1 kHz
Measuring accuracy: ±(0.3 %rdg + 3 dgt)
Ae = 0.3 %rdg
Z
M
= 1/(2 x 3.14 x 1000 x 180 x 10 -9 )
= 884.6 Ω
Re = ±0.003 x 884.6
= ± 2.65 Ω
Accuracy of Q value Qe ：
Condition: Q ・ De < 1
Ex. Inductor to be measured: 180 μH
Test frequency: 10 kHz
Measuring accuracy: ±(0.5 %rdg + 3 dgt)
Assumption: De = Ae = ±0.005
Measured Q value: 20
Qe = ±20 x 20 x 0.005 / (1- 20 x 0.005)
= 2.22
4-terminal measurement with guard shielding:
The DUT measuring leads are implemented by 4-terminal
measurement. It is necessary to perform the OPEN/SHORT
calibration to obtain the accuracy shown above. The measuring leads
for DUT should be as short as possible. If long extended cables are
used, the guard shielding will be necessary.
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