Agilent Technologies B1500A User Manual page 116

Installation
Connecting Measurement Devices
Connections for High Current Measurements
When you force or measure a large current, you may want to use a Kelvin (4-wire)
connection to eliminate the residual resistance effects of test leads and contacts. For
example, you can use the following connections as Kelvin connections on the test
fixture.
Examples: Kelvin Connection
To cancel the effects of the residual resistance, test leads must be connected as close
as possible to the DUT.
3- 42 Agilent B1500A User's Guide, Edition 10