Hioki DM7275 Series - Switching The Input Resistance

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Switching the Input Resistance
6.4 Switching the Input Resistance
The voltmeter’s input resistance (internal resistance) can be switched.
(Measurement screen) MENU > MEAS > INPUT Z
AUTO Auto mode
• 100 mV to 10 V range:
10 G
Ω
or greater
(Hi-Z will be displayed on the
screen; see gure to right.)
• 100 V range and 1000 V range:
10 M
Ω
10M
Ω
Fixed at 10 M
Ω
(default setting).
Measurement
range
AUTO input resistance setting
10M
Ω
input resistance setting
100 mV
1000 mV
10 V
V
10 GΩ<
10 G
Ω
<
V
10 MΩ
100 V
1000 V
V
10 MΩ
When the input resistance is set to 10 M
Ω
, measurement is more prone to the effects of the measurement
target’s output resistance (signal source resistance).
Example: a coin-shaped battery with an output resistance of 1 k
Ω
and an open voltage of 3 V when
measured with the 10M
Ω
input resistance setting
V
9997.23
k1M10
M10
=×
Ω+Ω
Ω
V
R
OUT
R
IN
V
V
RR
R
INOUT
IN
+
Output
resistance
Voltage
Input resistance
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