NF ZM2371, Instruction Manual

Page: 64 / 255

3.5 Basic Operations
3-34 ZM2371/ZM2372
When the ALC function (CV or CC) is enabled, the LCR meter repeats the measurement
while adjusting the measurement signal level until the following values are obtained.
CV: Voltage monitored value is the set value

1% of set value.
CC: Current monitored value is the set value  (1% of set value + 0.02% of max. drive /
detection current in measurement range)
Accordingly, the measurement will take time.
When the specified voltage or current cannot be obtained even though the adjustment of
measurement signal level is repeated, an error occurs and the measured value becomes ALC
Err.
When the measurement range is set to “auto selection”, first the measurement range is
adjusted, and then the measurement signal level in that measurement range is adjusted. In
that measurement range, the measurement signal level is changed in a range of 10mVrms to
5Vrms to adjust to the specified voltage or current.
！
CAUTION
With the constant voltage function enabled, if the DUT is removed after small
impedance was measured, the maximum 5Vrms signal may be output.
With the constant current function enabled, if the measurement terminals are
opened, the maximum 5Vrms signal may be output.
Automatic adjustment of voltage or current by the ALC is restricted as follows:
1) ALC function may fail if the voltage-current characteristics of DUT are extremely
nonlinear.
2) The output impedance does not become 5

even if the minimum output impedance is set
to 5  when the ALC function is enabled. The output impedance will become 100  or 25 
following the measurement range, same as when the minimum output impedance is set to
25
 .
3) Due to the characteristic variations of LCR meter, the voltage or current may not be
adjusted to settable maximum voltage or maximum current.