With regard to: U3089, U3589, U368x, U168x, U118x
U3089, U3589, U3681, U3687, U3689 and U1681 energy meters are suitable for operation with line frequencies of 50 and 60 Hz.
The bus-compatible energy meters for 3-phase measurement can be operated with a line frequency for 60 Hz under the following conditions:
U1187, U1687 - at least 3 phase voltages must be applied
U1189, U1689 - at least 2 phase voltages must be applied
As specified in meter standard EN61036, operation with only one phase voltage in a 4-wire system or two phase voltages in a 3-wire system is impermissible.