QuadTech 1657 RLC Digibridge Instruction Manual page 19

Figure 3-2. R L C basic accuracy as a percent of reading. Heavy lines (solid and dotted) represent best
choice of range. Range 2 is dotted. Notice that Land C scales above graph are for 120 Hz (*equally valid for
100 Hz) and the 2 below graph are for 1 kHz. The DQ accuracy factor (right-hand scale) is the multiplier
that, applied to the DQ Basic Accuracy, yields complete DQ accuracy, for range extensions as well as the
basic ranges (where RLC accuracy is 0.2%).
of quadrature impedance, multiply each basic accuracy value by the RLC
accuracy factor; see below.
Figure 3-3 shows the RLC accuracy factor, which depends on D or Q.
For example, suppose a capacitor measured at
1 kHz has C = 400 uF and D = 0.5. The R LC basic accuracy is 0.4% and
the R LC accuracy factor is 1.5. Therefore, the accuracy of the C
measurement is :+/-0.6%. Notice that the
D or Q of a resistor (if significant) can be measured by selecting the C/D or
L/Q FUNCTION.
Figure 3-4 shows the basic DQ accuracy, which is simple function of
D or Q. For D read the lower scale and lower curve. For Q read the upper
scale and upper curve. The basic DQ accuracy is valid only if
measurements are made on one of the 3 basic ranges (where RLC
accuracy
is best). Otherwise, multiply basic DQ accuracy by the DQ accuracy
factor, shown on the right of the "RLC basic accuracy" graph. In the
example of C = 400 uF, D = 0.5, the basic D accuracy is 0.5% and the D
accuracy factor is 2. Therefore, the accuracy of the D measurement is :+/-1%
OPERATION 3-5