Further information for ABB Automation E236-US2.1 (2CDE165011R2001)
All measuring inputs must be connected to one phase each. If no three-phase
measurement is performed, the measuring inputs must be connected to one phase in order to
apply the required voltage to all measuring inputs. If a load
causes a reverse voltage that exceeds the threshold value Us, phase failures cannot
be identified.
A neutral conductor must always be connected!