Keysight Technologies 3458A Guide D'utilisation page 90

3 Configuring for Measurements
environment. You can enhance the accuracy of 2-wire ohms measurements with
the NULL math operation (refer to
Figure 3-3
specify 2-wire ohms measurements using the OHM command. For example, to
specify 2-wire ohms measurements on the 1 kW range, send:
OUTPUT 722;"OHM 1E3"
Figure 3-3
4-wire ohms
The 4-wire ohms mode eliminates the measurement error caused by test lead
resistance. In 2-wire ohms, the voltage measurement is made across the
combined resistance of the test leads and the unknown resistance. In 4-wire
ohms, the voltage is measured across the unknown resistance only, not the
combined resistance. This is important when the test lead resistance is high in
comparison to the resistance being measured.
connections for 4-wire ohms measurements. You specify 4-wire ohms
measurements using the OHMF command. For example, to specify 4-wire ohms
measurements on the 10 MW range, send:
OUTPUT 722; "OHMF 10E6"
90
shows the front connections for 2-wire ohms measurements. You
2-Wire ohms measurement connections
NULL in Chapter 4 for more information).
Figure 3-4
Keysight 3458A User's Guide
shows the front