User guide

MEASUREMENT OPERATION
18
Note
 In each range, the Meter has an input impedance of 10MΩ except for the mV
range which has an input impedance of 3000MΩ. This loading effect can cause
measurement errors in high impedance circuits. If the circuit impedance is less
than or equal to 10kΩ, the error is negligible (0.1% or less).
 For GDM-398: When measuring mV, you must press RANGE manually to enter
mV range.
 For the GDM-397: The AC/DC voltage measurement ranges and the AC/DC
mV measurement ranges are separated. When the rotary switch is in the AC/DC
voltage position (V ), the RANGE button can be used to switch between the
different voltage measurement ranges. Similarly, when the rotary switch in the
AC/DC mV position (mV ), the RANGE button can be used to switch between
the different mV measurement ranges.
 When voltage measurement has been completed, disconnect the testing leads
from the DUT and remove the testing leads from the input terminals of the
Meter.