Keysight E4981A Programming Manual page 18

Overview of Remote Control
Types of Remote Control System
You must install Keysight I/O Libraries Suite in the external controller in
advance.
Use Keysight I/O Libraries Suite 15.0 or higher.
For further information on I/O Libraries Suite, see the Keysight I/O Libraries
Suite manual.
Keysight I/O Libraries Suite may not be available for certain external
controllers or OS versions. For further details, refer to the Help guidance
for Keysight I/O Libraries Suite.
18 Keysight E4981A 120 Hz/1 kHz/1 MHz Capacitance Meter