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Keysight E1412A Digital Multimeter User Guide
Keysight E1412A Multimeter Application Information
DC Voltage Measurements
Loading Errors (dc volts)
Measurement loading errors occur when the resistance of the device- under-test
(
DUT
) is an appreciable percentage of the multimeter's own input resistance. The
diagram below shows this error source.
To reduce the effects of loading errors, and to minimize noise pickup, you can set
the multimeter's input resistance to greater than 10G
for the 100mVdc, 1Vdc,
and 10Vdc ranges. The input resistance is maintained at 10M
for the 100Vdc
and 300Vdc ranges.
Leakage Current Errors
The multimeter's input capacitance will “charge up” due to input bias currents
when the terminals are open-circuited (if the input resistance is 10G
). The
multimeter's measuring circuitry exhibits approximately 30pA of input bias
current for ambient temperatures from 0°C to 30°C. Bias current will double (
2)
for every 8°C change in ambient temperature above 30°C. This current generates
small voltage offsets dependent upon the source resistance of the
Table 2-1
Thermoelectric Voltages
Copper-to-
Approx.
V/
C
Copper
<0.3
Gold
0.5
Silver
0.5
Brass
3
Beryllium Copper
5
Aluminum
5
Kovar or Alloy 42
40
Silicon
500
Copper-Oxide
1000
Cadmium-Tin Solder
0.2
Tin-Lead Solder
5
The E1412A input
terminals are
copper alloy.
Summary of Contents for E1412A
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