Keysight U1231A Guide De Démarrage Rapide page 16

VZ measurement
LOW
4
Energuzed wiring
3
Adjacent unused wiring
2
1
Ghost voltages can be caused by capacitive
NOTE
coupling between energized wiring and adjacent
unused wiring. Use the VZ function to eliminate
LOW
ghost or induced voltages in your measurements.
16 Keysight U1231A/U1232A/U1233A Quick Start Guide